Fix RS1038 related warnings found in Interop source generators

[buyaa-n]

Fix warnings found with RS1038 analyzer

Recent analyzer updates flown to the runtime repo having build failures related to RS1038: Compiler extensions should be implemented in assemblies with compiler-provided references. The warnings looks valid and needs a proper fix, for now they are suppressed.

Sample log:

warning RS1038: This compiler extension should not be implemented in an assembly containing a reference to Microsoft.CodeAnalysis.Workspaces. The Microsoft.CodeAnalysis.Workspaces assembly is not provided during command line compilation scenarios, so references to it could cause the compiler extension to behave unpredictably.

Related to #87768
CC @jkoritzinsky

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Issue Details

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Fix warnings found with RS1038 analyzer

Recent analyzer updates flown to the runtime repo having build failures related to RS1038: Compiler extensions should be implemented in assemblies with compiler-provided references. The warnings looks valid and needs a proper fix, for now they are suppressed.

Sample log:

warning RS1038: This compiler extension should not be implemented in an assembly containing a reference to Microsoft.CodeAnalysis.Workspaces. The Microsoft.CodeAnalysis.Workspaces assembly is not provided during command line compilation scenarios, so references to it could cause the compiler extension to behave unpredictably.

Related to #87768
CC @jkoritzinsky

Author:	buyaa-n
Assignees:	-
Labels:	area-System.Runtime.InteropServices
Milestone:	-

[jkoritzinsky]

This is due to the interop analyzers putting analyzers and code fixes into the same assembly. It looks like we need to split them into separate assemblies for the re-written RS1038 rule to be satisfied. Moving to .NET 9 as this is more infra work than anything else (as we're careful to not use the workspaces APIs in the analyzer or generator code).