Bump numpy

Bumps the pip group with 1 update in the /examples/separate_audio directory: [numpy](https://github.com/numpy/numpy).


Updates `numpy` from 1.18.5 to 1.22.0
- [Release notes](https://github.com/numpy/numpy/releases)
- [Changelog](https://github.com/numpy/numpy/blob/main/doc/RELEASE_WALKTHROUGH.rst)
- [Commits](numpy/numpy@v1.18.5...v1.22.0)

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

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

examples/separate_audio/requirements.txt

@@ -1,4 +1,4 @@
 fastnode
 # apt-get install ffmpeg
-numpy==1.18.5
+numpy==1.22.0
 spleeter