zephyr_mirror: Always run backend script from current directory.

While this technically removes functionality, it's rare that it would
be useful to do this.

Author: timabbott

zulip/integrations/zephyr/zephyr_mirror.py

@@ -49,7 +49,7 @@ def die(signal, frame):
 
 from zulip import RandomExponentialBackoff
 
-args = [os.path.join(options.root_path, "user_root", "zephyr_mirror_backend.py")]
+args = [os.path.join(os.path.dirname(os.path.realpath(__file__)), "zephyr_mirror_backend.py")]
 args.extend(sys.argv[1:])
 
 if options.sync_subscriptions: