Add trailing comments on multiline lists - editorconfig. (#28922)

Add trailing comments on multiline lists.

.editorconfig

@@ -1,4 +1,5 @@
 root = true
+
 [*]
 
 charset = utf-8
@@ -342,6 +343,7 @@ resharper_csharp_wrap_parameters_style = chop_if_long
 resharper_keep_existing_attribute_arrangement = true
 resharper_wrap_chained_binary_patterns = chop_if_long
 resharper_wrap_chained_method_calls = chop_if_long
+resharper_csharp_trailing_comma_in_multiline_lists = true
 
 [*.{csproj,xml,yml,yaml,dll.config,msbuildproj,targets,props}]
 indent_size = 2