Update EditorConfig.json with missing language rules

[seangwright]

Adds missing rules which currently are labeled as 'unknown' with this extension.

• https://docs.microsoft.com/en-us/dotnet/fundamentals/code-analysis/style-rules/ide0090
  • csharp_style_implicit_object_creation_when_type_is_apparent
• https://docs.microsoft.com/en-us/dotnet/fundamentals/code-analysis/style-rules/ide0062
  • csharp_prefer_static_local_function

[madskristensen]

Thanks