unblock select loop during reload of a sync worker

When reloading the worker canbe in the select loop and it will wait until timeout before handling any change. So make sure to wake up the loop before going further.

gunicorn/workers/base.py

@@ -123,6 +123,7 @@ class Worker(object):
             def changed(fname):
                 self.log.info("Worker reloading: %s modified", fname)
                 self.alive = False
+                os.write(self.PIPE[1], b"1")
                 self.cfg.worker_int(self)
                 time.sleep(0.1)
                 sys.exit(0)