Bump requests from 2.27.1 to 2.28.1 (#973)

Bumps [requests](https://github.com/psf/requests) from 2.27.1 to 2.28.1.
- [Release notes](https://github.com/psf/requests/releases)
- [Changelog](https://github.com/psf/requests/blob/main/HISTORY.md)
- [Commits](psf/requests@v2.27.1...v2.28.1)

---
updated-dependencies:
- dependency-name: requests
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements_dev.txt

@@ -10,7 +10,7 @@ pytest-cache==1.0
 pytest-cov==3.0.0
 pytest-mock<3.8.3
 recommonmark==0.7.1
-requests==2.27.1
+requests==2.28.1
 requests-mock==1.9.3
 sphinx==4.3.2
 sphinx-rtd-theme==1.0.0