[NETSDKE2E][Green] The refresh test button in the test explorer disappear on Mac and Linux.

[yinjiehe01]

REGRESSION INFO
Also repro on April release Stable build.
But this issue does not repro on Windows.

INSTALL STEP

1.Install SDK 10.0.300 on Linux.
2.Install latest VS Code and C# dev kit May prerelease 3.21.203 (C# May release 2.140.9) extension.

REPRO STEPS

1. Click the Create .NET Project button and select a UT test project.
2. Click the TESTING explorer and observe.

Expected
The refresh test button exists.

Actual
The refresh test button disappears on Mac and Linux.

[yinjiehe01]

Close this issue because a solution has been found.
Uncheck the dotnet.testWindowsenablenextTest in setting can resolve this issue.