Sort global System usings before other global usings

[vipentti]

Fixes #1003

[vipentti]

I'm not sure why either of the failed checks actually fail.

Check Formatting seems to fail to something. Locally formatting checks out okay except for the expected after running other tests:

Error ./Src/CSharpier.Cli.Tests/bin/Debug/net8.0/TestFiles/CheckUnformatted.cs - Was not formatted.
  The file did not end with a single newline.
Formatted 302 files in 1254ms.

Without that

dotnet csharpier . --check 
Formatted 301 files in 813ms.

Run Tests seems to fail due so some unrelated issue:

 Unhandled exception: System.AggregateException: One or more errors occurred. 
 (The process cannot access the file '/tmp/1fd44a6a-9e27-45bb-ad6c-bcaaf578e68d/project.assets.json' because it is being used by another process.)

[shocklateboy92]

The tests are actually failing due to dotnet/sdk#35989

[shocklateboy92]

@belav can you take a look / update to the latest .net RC? That should fix it.

[belav]

@belav can you take a look / update to the latest .net RC? That should fix it.

I've been getting past it for now by just running the action again, it usually works the second time. I can hopefully get things updated to the new net8 this weekend.

@vipentti thanks for the fix!