[FIX] queue_job: repoint default_env to SUPERUSER in runjob

runjob is declared auth="none", so _auth_method_none pins request.env
and transaction.default_env to a uid=None env. `env = http.request.env(
user=SUPERUSER_ID)` only creates a local superuser env, leaving the
default_env as uid=None. Any flush that goes through
Transaction.flush() -> default_env.flush_all() then recomputes stored
fields as uid=None and fails on anything dereferencing self.env.user.

`http.request.update_env(user=SUPERUSER_ID)` additionally sets
transaction.default_env to the superuser env.

Closes #922

Author: dannyadair

queue_job/controllers/main.py

@@ -215,7 +215,8 @@ def _get_failure_values(cls, job, traceback_txt, orig_exception):
     )
     def runjob(self, db, job_uuid, **kw):
         http.request.session.db = db
-        env = http.request.env(user=SUPERUSER_ID)
+        http.request.update_env(user=SUPERUSER_ID)
+        env = http.request.env
         job = self._acquire_job(env, job_uuid)
         if not job:
             return ""