Bump numpy from 1.18.1 to 1.19.1

Bumps [numpy](https://github.com/numpy/numpy) from 1.18.1 to 1.19.1.
- [Release notes](https://github.com/numpy/numpy/releases)
- [Changelog](https://github.com/numpy/numpy/blob/master/doc/HOWTO_RELEASE.rst.txt)
- [Commits](numpy/numpy@v1.18.1...v1.19.1)

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

Author: dependabot[bot]

requirements.txt

@@ -1,5 +1,5 @@
 # base
-numpy==1.18.1
+numpy==1.19.1
 scipy==1.4.1
 matplotlib==3.3.1
 scikit-learn==0.23.2