Revert "Disable nogcregion (dotnet#100167)"

This reverts commit b31f952.

Author: markples

src/tests/issues.targets

@@ -17,9 +17,6 @@
         <ExcludeList Include = "$(XunitTestBinBase)/JIT/opt/SSA/MemorySsa/**">
             <Issue>https://github.com/dotnet/runtime/issues/86112</Issue>
         </ExcludeList>
-        <ExcludeList Include = "$(XunitTestBinBase)/GC/API/NoGCRegion/Callback_Svr/**">
-            <Issue>https://github.com/dotnet/runtime/issues/100149</Issue>
-        </ExcludeList>    
     </ItemGroup>
 
     <!-- All OS/Arch CoreCLR excludes -->