Bugfix :: Coloring for case testers and with

[T-Gro]

Coloring issues identified at #19252 (comment) and
#19252 (comment)

[github-actions]

❗ Release notes required

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✅ Found changes and release notes in following paths:

Change path	Release notes path	Description
src/Compiler	docs/release-notes/.FSharp.Compiler.Service/10.0.300.md

[T-Gro]

@kerams :

Another thing which fell out of the implementation is that we can decide to color the union case accessor the same we color its constructor and the case itself, i.e. not like a property.

I can see reasoning for both "its all artifacts of the case - declaration, constructor, tester" as well as "its just another member".

See here how it si colored differently from the custom prop., I kind of like it. WDYT about it?