Merge master to features/lspClassifications

Move C# editorconfig diagnostic support API to CompilationOptions, instead of SyntaxTree

Fix crash in the preview of a code action that modified an .editorconfig

Add temporary support for colorization in LSP hover

For reasons that aren't entirely clear, when we create a preview of
a code fix, we remove and re-add documents that are being changed when
we produce the PreviewWorkspace. This process had an bug which meant
that the file path of an .editorconfig got dropped, so the resultant
.editorconfig document path was null. This later caused a crash if
the diagnostic engine, when processing the PreviewWorkspace's
new solution, tried asking for a Compilation, since the null path would
get passed to AnalyzerConfig.Parse(), and it would throw.

This was exposed by #45076; until then if you had a preview of just
an .editorconfig file, nothing would actually be analyzed and so
nothing asked for the Compilation. The crash is "fixed" by #44331 in
that asking for a Compilation no longer results in a call to
AnalyzerConfig.Parse(); you have to ask for a Compilation and then do
something with a semantic model. By luck, that doesn't happen in the
common repro, but more obscure things absolutely could still fail.

This is being tested by the integration test being added in #46639. We
don't really have a good unit tests here as far as I can tell, but even
then a unit test really doesn't validate any of the end-to-end here.

Fixes https://devdiv.visualstudio.com/DevDiv/_workitems/edit/1162464

Fix issue where compiler host dropped connections under load

* Move null check above where the variable is used

* Fix formatting

Added interpolated strings to list of possible literals - Inline Parameter Name Hints

Avoid reporting progress for index updates

Enable PasteCommandWithInteractiveFormatAsBoxCopy

Enable CSharpOutliningTagger_RegionIsDefinition

Remove unnecessary use of 'Option Strict Off'

Revert "don't run CI on changes that do not change code"

Delete a workaround from InvisibleEditor.cs