Add --self-contained and --no-self-contained options to dotnet test

[Copilot]

Running dotnet test --runtime <RID> produces warning NETSDK1179 requiring --self-contained or --no-self-contained, but these options were not supported by the test command.

Changes

• TestCommandParser.cs: Added SelfContainedOption and NoSelfContainedOption to both VSTest and Microsoft Testing Platform command parsers
• TestCommand.cs & MicrosoftTestingPlatformTestCommand.cs: Added mutual exclusion validation using existing CommonOptions.ValidateSelfContainedOptions()
• Tests: Added coverage for both options individually and mutual exclusion validation

Usage

# Suppress NETSDK1179 warning with explicit self-contained behavior
dotnet test --runtime win-x86 --no-self-contained

# Or for self-contained tests
dotnet test --runtime win-x86 --self-contained

The implementation follows the same pattern as dotnet build, dotnet publish, and dotnet run. Options forward as MSBuild properties (SelfContained=true/false and _CommandLineDefinedSelfContained=true).

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Add '--self-contained' and '--no-self-contained' options to dotnet test command</issue_title>
<issue_description>### Is your feature request related to a problem? Please describe.

Running:

dotnet test --configuration Release --runtime win-x86 --collect "XPlat Code Coverage"

Gives the following warning:

warning NETSDK1179: One of '--self-contained' or '--no-self-contained' options are required when '--runtime' is used.

However the dotnet test command does not support the --self-contained or --no-self-contained options.

Describe the solution you'd like

Add --self-contained and --no-self-contained option to dotnet test command.

Could be considered an alternate solution to #27151
</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Add '--self-contained' and '--no-self-contained' options to dotnet test command #31066

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[Youssef1313]

Is the intent here to do that for MTP only? Or both MTP and VSTest?
I'm not sure if any of this will work well with VSTest. Looping @nohwnd in as well.