Recursive invocations for node --run in Windows are incorrect

The tests for `node --run` named `run recurse -> run start --watch` and `run recurse -> run start --watch --extra` fail on Windows. It seems to be a similar problem to what Yarn does, where when you do recursive calls, the environment variable that says what script we're in (`NODE_RUN_SCRIPT_NAME` in this case) reflects the first call, instead of the last.

This is very likely a Windows-specific Node bug, so the next step is to confirm it and file an issue. Then we can un-skip those tests in Windows once fixed.