Update Roslyn to a version which uses Immutable v7 (#16545)

Author: T-Gro

eng/Versions.props

@@ -91,7 +91,7 @@
     <SystemRuntimeCompilerServicesUnsafeVersion>6.0.0</SystemRuntimeCompilerServicesUnsafeVersion>
     <SystemValueTupleVersion>4.5.0</SystemValueTupleVersion>
     <!-- Versions for package groups -->
-    <RoslynVersion>4.6.0-2.23126.2</RoslynVersion>
+    <RoslynVersion>4.6.0-3.23329.3</RoslynVersion>
     <VisualStudioEditorPackagesVersion>17.7.25-preview</VisualStudioEditorPackagesVersion>
     <MicrosoftVisualStudioShellPackagesVersion>17.7.35338-preview.1</MicrosoftVisualStudioShellPackagesVersion>
     <VisualStudioProjectSystemPackagesVersion>17.7.58-pre</VisualStudioProjectSystemPackagesVersion>