refs and cleanup

Author: SimonCropp

src/.editorconfig

@@ -189,7 +189,7 @@ resharper_arrange_object_creation_when_type_evident_highlighting = error
 resharper_arrange_object_creation_when_type_not_evident_highlighting = error
 resharper_arrange_redundant_parentheses_highlighting = error
 resharper_arrange_static_member_qualifier_highlighting = error
-resharper_arrange_this_qualifier_highlighting = hint
+resharper_arrange_this_qualifier_highlighting = error
 resharper_arrange_type_member_modifiers_highlighting = none
 resharper_built_in_type_reference_style_for_member_access_highlighting = hint
 resharper_built_in_type_reference_style_highlighting = hint

src/Directory.Packages.props

@@ -8,8 +8,8 @@
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
     <PackageVersion Include="NUnit" Version="4.1.0" />
     <PackageVersion Include="NUnit3TestAdapter" Version="4.5.0" />
-    <PackageVersion Include="Polyfill" Version="5.5.2" />
-    <PackageVersion Include="ProjectDefaults" Version="1.0.130" />
+    <PackageVersion Include="Polyfill" Version="5.6.0" />
+    <PackageVersion Include="ProjectDefaults" Version="1.0.131" />
     <PackageVersion Include="System.Collections.Immutable" Version="8.0.0" />
     <PackageVersion Include="System.Memory" Version="4.5.5" />
     <PackageVersion Include="System.Threading.Tasks.Extensions" Version="4.5.4" />