Bump numpy from 1.18.2 to 1.18.3

Bumps [numpy](https://github.com/numpy/numpy) from 1.18.2 to 1.18.3.
- [Release notes](https://github.com/numpy/numpy/releases)
- [Changelog](https://github.com/numpy/numpy/blob/master/doc/HOWTO_RELEASE.rst.txt)
- [Commits](numpy/numpy@v1.18.2...v1.18.3)

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

requirements.txt

@@ -14,4 +14,4 @@ icalendar==4.0.5
 sqlalchemy==1.3.15
 filelock==3.0.12
 alembic==1.4.2
-numpy==1.18.2
+numpy==1.18.3