GivenDotnetTest Failures

[nagilson]

In the past week, we've seen a number of failures from sdk\test\dotnet-test.Tests\GivenDotnetTestBuildsAndRunsTests.cs -- it is failing in main almost 80% of the time in one test or another. This is a relatively new issue as they're new.

For example, we saw RunMultipleTestProjectsWithDifferentFailures_ShouldReturnOneAsExitCode fail with the following:

   Assert.Matches() Failure: Pattern not found in value
Regex: ".+Debug\\\\net10.0\\\\TestProject\\.dll\\s+\\(net1"···
Value: "  Determining projects to restore...\r\n  Restored"···

And another example is ``RunMultipleTestProjectsWithDifferentFailures_ShouldReturnExitCodeGenericFailure`, which failed here:
#46916

net 00:01:14.37]     Microsoft.DotNet.Cli.Test.Tests.GivenDotnetTestBuildsAndRunsTests.RunMultipleTestProjectsWithDifferentFailures_ShouldReturnExitCodeGenericFailure(configuration: "Release") [FAIL]
[xUnit.net 00:01:14.37]       Assert.Matches() Failure: Pattern not found in value
[xUnit.net 00:01:14.37]       Regex: ".+Release\\\\net10.0\\\\OtherTestProject\\.dll\\s+"···
[xUnit.net 00:01:14.37]       Value: "Running tests from C:\\h\\w\\B0DB094E\\t\\dotnetSd"···
[xUnit.net 00:01:14.37]       Stack Trace:

cc @mariam-abdulla when you have an opportunity, please take a look at these tests. I will be disabling them for now because they are blocking PRs. Thanks for your help!