Bump numpy from 1.17.3 to 1.17.4 (#1097)

Bumps [numpy](https://github.com/numpy/numpy) from 1.17.3 to 1.17.4.
- [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/v1.17.3...v1.17.4)

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

requirements.txt

@@ -2,7 +2,7 @@ imbalanced-learn==0.5.0
 libmozdata==0.1.60
 matplotlib==3.1.1
 microannotate==0.0.18
-numpy==1.17.3
+numpy==1.17.4
 orjson==2.1.2
 pandas==0.25.3
 pydriller==1.9.2