Mentat

This happens both in vagrantbox and GitLab CI/CD.

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ERROR: Perform the tests of module service.
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Traceback (most recent call last):
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/engine/base.py", line 2285, in _wrap_pool_connect
    return fn()
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/pool/base.py", line 363, in connect
    return _ConnectionFairy._checkout(self)
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/pool/base.py", line 773, in _checkout
    fairy = _ConnectionRecord.checkout(pool)
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/pool/base.py", line 492, in checkout
    rec = pool._do_get()
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/pool/impl.py", line 139, in _do_get
    self._dec_overflow()
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/util/langhelpers.py", line 69, in __exit__
    exc_value, with_traceback=exc_tb,
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/util/compat.py", line 178, in raise_
    raise exception
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/pool/impl.py", line 136, in _do_get
    return self._create_connection()
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/pool/base.py", line 308, in _create_connection
    return _ConnectionRecord(self)
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/pool/base.py", line 437, in __init__
    self.__connect(first_connect_check=True)
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/pool/base.py", line 657, in __connect
    pool.logger.debug("Error on connect(): %s", e)
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/util/langhelpers.py", line 69, in __exit__
    exc_value, with_traceback=exc_tb,
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/util/compat.py", line 178, in raise_
    raise exception
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/pool/base.py", line 652, in __connect
    connection = pool._invoke_creator(self)
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/engine/strategies.py", line 114, in connect
    return dialect.connect(*cargs, **cparams)
  File "/var/mentat/venv/lib/python3.7/site-packages/sqlalchemy/engine/default.py", line 488, in connect
    return self.dbapi.connect(*cargs, **cparams)
  File "/var/mentat/venv/lib/python3.7/site-packages/psycopg2/__init__.py", line 126, in connect
    conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
psycopg2.OperationalError: connection to server at "localhost" (::1), port 5432 failed: FATAL:  remaining connection slots are reserved for non-replication superuser connections