test//erasure-code/TestErasureCodeLrc: free allocated CrushWrapper

in TestErasureCodeLrc.cc, we create a `CrushWrapper` without
destroying and freeing it. and ASan points this out:
```
Indirect leak of 72000 byte(s) in 1000 object(s) allocated from:
    #0 0x559e00acc2bd in operator new(unsigned long) (/home/jenkins-build/build/workspace/ceph-pull-requests/build/bin/unittest_erasure_code_lrc+0x1ed2bd) (BuildId: 1cd93d0f231006242239eb0d81a8d677e36aeba2)
    #1 0x559e00b2bb76 in __gnu_cxx::new_allocator<std::_Rb_tree_node<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >::allocate(unsigned long, void const*) /usr/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/ext/new_allocator.h:127:27
    #2 0x559e00b2bb00 in std::allocator<std::_Rb_tree_node<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >::allocate(unsigned long) /usr/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/allocator.h:185:32
    #3 0x559e00b2bb00 in std::allocator_traits<std::allocator<std::_Rb_tree_node<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > > >::allocate(std::allocator<std::_Rb_tree_node<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >&, unsigned long) /usr/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/alloc_traits.h:464:20
    #4 0x559e00b2b9d1 in std::_Rb_tree<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int>, std::_Select1st<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> >, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >::_M_get_node() /usr/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/stl_tree.h:561:16
    #5 0x559e00b2aae4 in std::_Rb_tree_node<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> >* std::_Rb_tree<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int>, std::_Select1st<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> >, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >::_M_create_node<std::piecewise_construct_t const&, std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&>, std::tuple<> >(std::piecewise_construct_t const&, std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&>&&, std::tuple<>&&) /usr/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/stl_tree.h:611:23
    #6 0x559e00b29520 in std::_Rb_tree_iterator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > std::_Rb_tree<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int>, std::_Select1st<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> >, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >::_M_emplace_hint_unique<std::piecewise_construct_t const&, std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&>, std::tuple<> >(std::_Rb_tree_const_iterator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> >, std::piecewise_construct_t const&, std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&>&&, std::tuple<>&&) /usr/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/stl_tree.h:2431:19
    #7 0x559e00b255c2 in std::map<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, int, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >::operator[](std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) /usr/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/stl_map.h:501:15
    #8 0x559e00b188da in CrushWrapper::set_item_name(int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) /home/jenkins-build/build/workspace/ceph-pull-requests/src/crush/CrushWrapper.h:466:7
    #9 0x7feb54a4dcc2 in CrushWrapper::insert_item(ceph::common::CephContext*, int, float, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::map<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > > const&, bool) /home/jenkins-build/build/workspace/ceph-pull-requests/src/crush/CrushWrapper.cc:1119:5
    #10 0x559e00ada922 in ErasureCodeTest_create_rule_Test::TestBody() /home/jenkins-build/build/workspace/ceph-pull-requests/src/test/erasure-code/TestErasureCodeLrc.cc:127:5
    #11 0x559e00c0e0a6 in void testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) /home/jenkins-build/build/workspace/ceph-pull-requests/src/googletest/googletest/src/gtest.cc:2605:10
```

so, in this change, let's manage the lifecycle of the `CrushWrapper`
instance with a smart pointer, so that it is destroyed and free'd
properly, and this should silence the ASan warning.

Signed-off-by: Kefu Chai <[email protected]>

src/test/erasure-code/TestErasureCodeLrc.cc

@@ -16,6 +16,7 @@
  */
 
 #include <errno.h>
+#include <memory>
 #include <stdlib.h>
 
 #include "crush/CrushWrapper.h"
@@ -91,7 +92,7 @@ TEST(ErasureCodeLrc, parse_rule)
 
 TEST(ErasureCodeTest, create_rule)
 {
-  CrushWrapper *c = new CrushWrapper;
+  auto c = std::make_unique<CrushWrapper>();
   c->create();
   int root_type = 3;
   c->set_type_name(root_type, "root");