Bump numpy from 1.16.4 to 1.22.0

Bumps [numpy](https://github.com/numpy/numpy) from 1.16.4 to 1.22.0.
- [Release notes](https://github.com/numpy/numpy/releases)
- [Changelog](https://github.com/numpy/numpy/blob/main/doc/HOWTO_RELEASE.rst)
- [Commits](https://github.com/numpy/numpy/compare/v1.16.4...v1.22.0)

---
updated-dependencies:
- dependency-name: numpy
  dependency-type: direct:production
...

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

requirements.txt

@@ -1,6 +1,6 @@
 textrank4zh==0.3
 lxml==4.6.3
-numpy==1.16.4
+numpy==1.22.0
 wordcloud==1.5.0
 matplotlib==3.1.1
 Flask==1.1.1