Bump sqlalchemy from 1.3.12 to 1.3.13

Bumps [sqlalchemy](https://github.com/sqlalchemy/sqlalchemy) from 1.3.12 to 1.3.13.
- [Release notes](https://github.com/sqlalchemy/sqlalchemy/releases)
- [Changelog](https://github.com/sqlalchemy/sqlalchemy/blob/master/CHANGES)
- [Commits](https://github.com/sqlalchemy/sqlalchemy/commits)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

requirements.txt

@@ -8,7 +8,7 @@ pytest-mock==2.0.0
 pytest-cov==2.8.1
 pyyaml==5.3
 requests==2.22.0
-sqlalchemy==1.3.12
+sqlalchemy==1.3.13
 SQLAlchemy-Utils==0.36.1
 prometheus_client==0.7.1
 uWSGI==2.0.18