Bump nokogiri from 1.10.1 to 1.13.4

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.1 to 1.13.4.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/v1.13.4/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.10.1...v1.13.4)

---
updated-dependencies:
- dependency-name: nokogiri
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile.lock

@@ -189,9 +189,11 @@ GEM
     mime-types (3.1)
       mime-types-data (~> 3.2015)
     mime-types-data (3.2016.0521)
-    mimemagic (0.3.2)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.1)
-    mini_portile2 (2.4.0)
+    mini_portile2 (2.8.0)
     minitest (5.11.3)
     msgpack (1.2.4)
     multi_json (1.13.1)
@@ -201,8 +203,9 @@ GEM
     net-ssh (5.0.1)
     netrc (0.11.0)
     nio4r (2.3.1)
-    nokogiri (1.10.1)
-      mini_portile2 (~> 2.4.0)
+    nokogiri (1.13.4)
+      mini_portile2 (~> 2.8.0)
+      racc (~> 1.4)
     orm_adapter (0.5.0)
     paper_trail (9.1.1)
       activerecord (>= 4.2, < 5.3)
@@ -212,6 +215,7 @@ GEM
     puma (3.11.4)
     pundit (1.1.0)
       activesupport (>= 3.0.0)
+    racc (1.6.0)
     rack (2.0.6)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)