C# intellisense integration tests are flaky #70582
Description
Seeing increased failure rate in the following tests after recent VS update.
Roslyn.VisualStudio.IntegrationTests.CSharp.CSharpIntelliSense.CtrlAltSpace
Roslyn.VisualStudio.IntegrationTests.CSharp.CSharpIntelliSense.AtNamespaceLevel
Roslyn.VisualStudio.IntegrationTests.CSharp.CSharpIntelliSense.VerifyCompletionListMembersOnStaticTypesAndCompleteThem
Roslyn.VisualStudio.IntegrationTests.CSharp.CSharpIntelliSense.NavigatingWithDownKey
Roslyn.VisualStudio.IntegrationTests.CSharp.CSharpIntelliSense.EnsureTheCaretIsVisibleAfterALongEdit
Roslyn.VisualStudio.IntegrationTests.CSharp.CSharpSignatureHelp.ExplicitSignatureHelpDismissesCompletion
Roslyn.VisualStudio.IntegrationTests.CSharp.CSharpReplIntellisense.VerifyCommitCompletionOnTopLevel
Roslyn.VisualStudio.IntegrationTests.CSharp.CSharpIntelliSense.XmlDocCommentIntelliSense
Roslyn.VisualStudio.IntegrationTests.CSharp.CSharpInteractiveCommands.VerifyReturnIndentCurrentLine
Roslyn.VisualStudio.NewIntegrationTests.CSharp.CSharpAutomaticBraceCompletion.Nested_AllKinds