jqueue: Setup inotify before checking for any job changes

Since the code waiting for job changes was modified to use inotify,
a race condition between checking for changes the first time and
setting up inotify occurs. If the job is modified after the check
but before inotify is active, changes would only be noticed after
the timeout (29 seconds in most cases) expired.

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>