Bump autobahn from 0.15.0 to 20.12.3 in /xerror

Bumps [autobahn](https://github.com/crossbario/autobahn-js) from 0.15.0 to 20.12.3.
- [Release notes](https://github.com/crossbario/autobahn-js/releases)
- [Changelog](https://github.com/crossbario/autobahn-js/blob/master/doc/changelog.md)
- [Commits](https://github.com/crossbario/autobahn-js/commits)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

xerror/requirements.txt

@@ -2,7 +2,7 @@ amqp==1.4.9
 anyjson==0.3.3
 asgi-redis==0.14.0
 asgiref==0.14.0
-autobahn==0.15.0
+autobahn==20.12.3
 billiard==3.3.0.23
 celery==3.1.23
 channels==0.17.0