Bump requests from 2.25.1 to 2.26.0 in /tests

Bumps [requests](https://github.com/psf/requests) from 2.25.1 to 2.26.0.
- [Release notes](https://github.com/psf/requests/releases)
- [Changelog](https://github.com/psf/requests/blob/master/HISTORY.md)
- [Commits](psf/requests@v2.25.1...v2.26.0)

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

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

Author: dependabot[bot]

tests/requirements.txt

@@ -1,3 +1,3 @@
-requests==2.25.1
+requests==2.26.0
 boto3==1.17.7
 pytest==6.2.4