Consolidated Fixes for C#/ C# Dev Kit extension user experience

This tracks the issues we need to tackle to fix the user experience for the Runtime extension experience in C#/DevKit:

Remaining top issues based on telemetry are timeouts, network issues, and powershell accounting for ~87% of failures. As such, our priority should be on improving those.

* [x] https://github.com/dotnet/vscode-dotnet-runtime/issues/1359
* [x] Investigate powershell further, make extension try 'pwsh' 'powershell' and 'powershell.exe' before reporting failure.
* [x] #1246
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* [ ] #1314
* [ ] Investigate auto-populating some error information into the issue reports
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* [x] #1338
* [ ] #1307
* [ ] #1308
* [x] #1301
* [x] #1304
* [x] #1302
* [x] #1303
* [x] #1305
* [x] #1306
* [x] #1309
* [x] https://github.com/dotnet/vscode-dotnet-runtime/pull/935