Bump numpy from 1.18.0 to 1.18.1 (#1229)

Bumps [numpy](https://github.com/numpy/numpy) from 1.18.0 to 1.18.1.
- [Release notes](https://github.com/numpy/numpy/releases)
- [Changelog](https://github.com/numpy/numpy/blob/master/doc/HOWTO_RELEASE.rst.txt)
- [Commits](https://github.com/numpy/numpy/compare/v1.18.0...v1.18.1)

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

requirements.txt

@@ -4,7 +4,7 @@ libmozdata==0.1.63
 lmdb==0.98
 matplotlib==3.1.2
 microannotate==0.0.19
-numpy==1.18.0
+numpy==1.18.1
 orjson==2.1.3
 pandas==0.25.3
 pydriller==1.10