Add issues.targets entry for UnitTest_GVM, #42924 (#43100)

src/tests/issues.targets

@@ -929,6 +929,9 @@
         <ExcludeList Include="$(XunitTestBinBase)/Loader/AssemblyDependencyResolver/AssemblyDependencyResolverTests/AssemblyDependencyResolverTests/*">
             <Issue>https://github.com/dotnet/runtime/issues/34905</Issue>
         </ExcludeList>
+        <ExcludeList Include="$(XunitTestBinBase)/Loader/classloader/MethodImpl/CovariantReturns/UnitTest/UnitTest_GVM/*">
+            <Issue>https://github.com/dotnet/runtime/issues/42924</Issue>
+        </ExcludeList>
     </ItemGroup>
 
     <!-- run.proj finds all the *.cmd/*.sh scripts in a test folder and creates corresponding test methods.