Disable unit tests

Disable a couple of unit tests that hard-code a string instead of using
the associated resource. This guarantees the unit tests will fail when
the users locale is set to anything other than en.

This is being tracked by #35631.

src/EditorFeatures/Test2/IntelliSense/CSharpCompletionCommandHandlerTests_Regex.vb

@@ -58,7 +58,7 @@ class c
         End Function
 
         <MemberData(NameOf(AllCompletionImplementations))>
-        <WpfTheory, Trait(Traits.Feature, Traits.Features.Completion)>
+        <WpfTheory(Skip := "https://github.com/dotnet/roslyn/issues/35631"), Trait(Traits.Feature, Traits.Features.Completion)>
         Public Async Function TestCaretPlacement(completionImplementation As CompletionImplementation) As Task
             Using state = TestStateFactory.CreateCSharpTestState(completionImplementation,
                 <Document><![CDATA[

src/EditorFeatures/Test2/IntelliSense/VisualBasicCompletionCommandHandlerTests_Regex.vb

@@ -34,7 +34,7 @@ end class
         End Function
 
         <MemberData(NameOf(AllCompletionImplementations))>
-        <WpfTheory, Trait(Traits.Feature, Traits.Features.Completion)>
+        <WpfTheory(Skip := "https://github.com/dotnet/roslyn/issues/35631"), Trait(Traits.Feature, Traits.Features.Completion)>
         Public Async Function TestCaretPlacement(completionImplementation As CompletionImplementation) As Task
             Using state = TestStateFactory.CreateVisualBasicTestState(completionImplementation,
                 <Document><![CDATA[