More ILLink formatting fixes

[sbomer]

Follow-up to #116941.

• Format ILCompiler.TrimmingTests
• Fix ILLink.RoslynAnalyzer generated tests
• Fix whitespace in comments and #if'd out code
• Fix whitespace in Roslyn Analyzer test strings
• Remove suppression for spacing around keywords
• Update expected warning locations for analyzer tests

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[Copilot]

Pull Request Overview

This PR applies broad formatting clean-ups across ILLink tests and related tooling code, aligning brace placement, using directives, comment whitespace, and editorconfig settings. It also updates expected diagnostic spans in Roslyn analyzer tests and corrects a few test directives.

• Reordered and grouped using directives for consistency.
• Standardized brace placement and indentation in methods and properties.
• Updated expected warning locations in ILLink.RoslynAnalyzer test files.
• Removed the SA1000 suppression and fixed whitespace in comments and #if directives.

Reviewed Changes

Copilot reviewed 41 out of 302 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/tools/illink/test/Mono.Linker.Tests.Cases/Substitutions/FeatureGuardSubstitutionsDisabled.cs	Reordered using directives.
src/tools/illink/test/Mono.Linker.Tests.Cases/Substitutions/FeatureGuardSubstitutions.cs	Reordered using directives.
src/tools/illink/test/Mono.Linker.Tests.Cases/Reflection/ObjectGetType.cs	Reordered using directives.
src/tools/illink/test/Mono.Linker.Tests.Cases/Reflection/EventHanderTypeGetInvokeMethod.cs	Standardized brace placement on overridden properties.
src/tools/illink/test/Mono.Linker.Tests.Cases/Extensibility/CustomStepCanFixAbstractMethods.cs	Fixed ordering of using for dependency namespaces.
src/tools/illink/test/Mono.Linker.Tests.Cases/DynamicDependencies/DynamicDependencyMethod.cs	Aligned whitespace around object creation and comments.
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/FieldDataFlow.cs	Reordered using directives.
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/ByRefDataflow.cs	Reordered using directives.
src/tools/illink/test/Mono.Linker.Tests.Cases/DataFlow/FeatureGuardAttributeDataFlow.cs	Reordered using directives.
src/tools/illink/test/Mono.Linker.Tests.Cases/Attributes/OnlyKeepUsed/UnusedAttributeOnReturnTypeIsRemoved.cs	Fixed whitespace in #if symbol.
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/UnconditionalSuppressMessageCodeFixTests.cs	Updated diagnostic spans for codefix tests.
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/RequiresUnreferencedCodeAnalyzerTests.cs	Updated diagnostic spans for analyzer tests.
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/RequiresDynamicCodeAnalyzerTests.cs	Updated diagnostic spans for analyzer tests.
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/RequiresAssemblyFilesAnalyzerTests.cs	Updated diagnostic spans for analyzer tests.
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/DynamicallyAccessedMembersCodeFixTests.cs	Updated diagnostic spans for codefix tests.
src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/DynamicallyAccessedMembersAnalyzerTests.cs	Updated diagnostic spans and fixed a malformed instantiation.
src/tools/illink/src/linker/Linker/TypeNameResolver.cs	Removed duplicate using.
src/tools/illink/src/ILLink.Shared/TrimAnalysis/Intrinsics.cs	Cleaned up comment prefixes.
src/tools/illink/external/Mono.Options/Options.cs	Reformatted class and method declarations to match style guide.
src/tools/illink/.editorconfig	Removed the suppression for SA1000 (spacing around keywords).
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/Tests/DocumentationSignatureParserTests.cs	Adjusted brace placement in tests.
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/TrimmingTestLogger.cs	Standardized brace placement in lock statements.
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/TrimmingDriver.cs	Standardized brace placement in loops and conditionals.
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/TrimmingArgumentBuilder.cs	Standardized brace placement in conditionals and loops.
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/TestRunner.cs	Standardized brace placement around try/catch.
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/TestInfraMultiFileCompilationModuleGroup.cs	Standardized brace placement in if statements.
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/TestCaseMetadataProvider.cs	Standardized brace placement and grouping of using.
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/TestCaseCompiler.cs	Standardized brace placement in method bodies.
src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/TestCaseCollector.cs	Standardized brace placement in loops and conditionals.

Comments suppressed due to low confidence (3)

src/tools/illink/test/Mono.Linker.Tests.Cases/DynamicDependencies/DynamicDependencyMethod.cs:198

• The instantiation syntax is malformed. It should be new Impl() with matching parentheses, e.g. var i = new Impl();.

            var i = new Impl ); // Avoid removal of non-implemented abstract methods

src/tools/illink/test/Mono.Linker.Tests.Cases/Attributes/OnlyKeepUsed/UnusedAttributeOnReturnTypeIsRemoved.cs:16

• The feature symbol is misspelled (IL_ASSEMBLY_AVAIABLE). It should read IL_ASSEMBLY_AVAILABLE to match the intended conditional compilation symbol.

#if IL_ASSEMBLY_AVAIABLE

src/tools/illink/test/ILLink.RoslynAnalyzer.Tests/DynamicallyAccessedMembersAnalyzerTests.cs:1415

• The object creation is missing its constructor invocation parentheses. It should be new CRequires<TOuter>() instead of new CRequires<TOuter>);.

                static CRequires<TOuter> Value => new CRequires<TOuter>);