Fix problem with __all__

src/betterproto/templates/header.py.j2

@@ -4,13 +4,13 @@
 # This file has been @generated
 
 __all__ = (
-    {%- for enum in output_file.enums -%}
+    {% for _, enum in output_file.enums|dictsort(by="key") %}
         "{{ enum.py_name }}",
     {%- endfor -%}
-    {%- for message in output_file.messages -%}
+    {% for _, message in output_file.messages|dictsort(by="key") %}
         "{{ message.py_name }}",
     {%- endfor -%}
-    {%- for service in output_file.services -%}
+    {% for _, service in output_file.services|dictsort(by="key") %}
         "{{ service.py_name }}Stub",
         "{{ service.py_name }}Base",
     {%- endfor -%}

tests/test_all_definition.py

@@ -16,4 +16,4 @@ def test_all_definition():
         "TestStub",
         "TestBase",
     )
-    assert enum.__all__ == ("Choice", "ArithmeticOperator", "Test")
+    assert enum.__all__ ==  ("ArithmeticOperator", "Choice", "Test")