⬆️ Bump kubernetes from 19.15.0 to 21.7.0

Bumps [kubernetes](https://github.com/kubernetes-client/python) from 19.15.0 to 21.7.0.
- [Release notes](https://github.com/kubernetes-client/python/releases)
- [Changelog](https://github.com/kubernetes-client/python/blob/master/CHANGELOG.md)
- [Commits](kubernetes-client/python@v19.15.0...v21.7.0)

---
updated-dependencies:
- dependency-name: kubernetes
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

requirements.txt

@@ -4,7 +4,7 @@ charset-normalizer==2.0.7
 click==8.0.3
 google-auth==2.3.3
 idna==3.3
-kubernetes==19.15.0
+kubernetes==21.7.0
 oauthlib==3.1.1
 pyasn1==0.4.8
 pyasn1-modules==0.2.8