Improve error handling of Server Actions with skewed deployment (#56618)

When there's a version skew, it might be possible that the Action's ID has changed and we're no longer able to locate it. By definition, that means we **should** return a 404 because it might have a different implementation now. Currently this throws a "cannot access workers of undefined" error which doesn't make sense.

Please review with whitespace ignored.

Author: shuding