Enable tests, since they are passing now

[fanyang-mono]

Fixes #51723

[radical]

AOT tests failed with:

[15:51:21] info: console.info: Arguments: --run,WasmTestRunner.dll,System.CodeDom.Tests.dll,-notrait,category=IgnoreForCI,-notrait,category=OuterLoop,-notrait,category=failing
[15:51:21] info: console.debug: MONO_WASM: Initializing mono runtime
[15:51:21] info: console.debug: MONO_WASM: ICU data archive(s) loaded, disabling invariant mode
[15:51:21] info: console.debug: mono_wasm_runtime_ready fe00e07a-5519-4dfe-b35a-f867dbaf2e28
[15:51:21] info: console.info: Initializing.....
[15:51:21] info: Discovering: System.CodeDom.Tests.dll (method display = ClassAndMethod, method display options = None)
[15:51:21] info: Discovered:  System.CodeDom.Tests.dll (found 1423 of 1424 test cases)
[15:51:21] info: Starting:    System.CodeDom.Tests.dll
[15:51:25] fail: 15:51:25.6527348 console.error: ThreadPool Callback threw an unhandled exception of type System.NullReferenceException
                 
Killed
['System.CodeDom.Tests' WORK ITEM LOG TRUNCATED: Command timed out, and was killed]

[fanyang-mono]

The test still fails sporadically.