Issue #363: Error in send_mail after upgrade to celery 4.4 (conservancy/kallithea)

[vyom]

New issue 363: Error in send_mail after upgrade to celery 4.4
https://bitbucket.org/conservancy/kallithea/issues/363/error-in-send_mail-after-upgrade-to-celery

vyom:

After upgrading Kallithea to latest version has send\_mail error.

```plaintext
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]: [2020-02-26 07:06:08,598: INFO/MainProcess] Received task: kallithea.lib.celerylib.send_email[25db2e2e-1a84-40bf-9561-cc7818f60ee4]
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]: [2020-02-26 07:06:08,599: DEBUG/MainProcess] TaskPool: Apply <function _fast_trace_task at 0x7f42bc2ad048> (args:('kallithea.lib.celerylib.send_email', '25db2e2e-1a84-40bf-9561-cc7818f60
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]: [2020-02-26 07:06:08,600: DEBUG/MainProcess] Task accepted: kallithea.lib.celerylib.send_email[25db2e2e-1a84-40bf-9561-cc7818f60ee4] pid:22129
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]: [2020-02-26 07:06:08,728: ERROR/ForkPoolWorker-2] Task kallithea.lib.celerylib.send_email[25db2e2e-1a84-40bf-9561-cc7818f60ee4] raised unexpected: AttributeError("'dict' object has no at
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]: Traceback (most recent call last):
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:   File "/home/kallithea/projects/kallithea/venv3/lib/python3.6/site-packages/celery/app/trace.py", line 385, in trace_task
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:     R = retval = fun(*args, **kwargs)
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:   File "/home/kallithea/projects/kallithea/venv3/lib/python3.6/site-packages/celery/app/trace.py", line 650, in __protected_call__
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:     return self.run(*args, **kwargs)
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:   File "/home/kallithea/projects/hg/kallithea/kallithea/lib/celerylib/__init__.py", line 67, in f_async
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:     f_org(*args, **kwargs)
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:   File "</home/kallithea/projects/kallithea/venv3/lib/python3.6/site-packages/decorator.py:decorator-gen-6>", line 2, in send_email
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:   File "/home/kallithea/projects/hg/kallithea/kallithea/lib/celerylib/__init__.py", line 127, in __wrapper
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:     ret = func(*fargs, **fkwargs)
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:   File "/home/kallithea/projects/hg/kallithea/kallithea/lib/celerylib/tasks.py", line 284, in send_email
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]:     email.utils.quote('%s (no-reply)' % author.full_name_or_username),
Feb 26 07:06:08 kallithea-5-3 kallithea-cli[22116]: AttributeError: 'dict' object has no attribute 'full_name_or_username'
```

‌