[deps] Update responses requirement from ~=0.25.8 to ~=0.26.0

Updates the requirements on [responses](https://github.com/getsentry/responses) to permit the latest version.
- [Release notes](https://github.com/getsentry/responses/releases)
- [Changelog](https://github.com/getsentry/responses/blob/master/CHANGES)
- [Commits](getsentry/responses@0.25.8...0.26.0)

---
updated-dependencies:
- dependency-name: responses
  dependency-version: 0.26.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements-test.txt

@@ -1,4 +1,4 @@
-responses~=0.25.8
+responses~=0.26.0
 freezegun~=1.5.5
 # Needed to test integrations
 openwisp-monitoring @ https://github.com/openwisp/openwisp-monitoring/archive/refs/heads/1.3.tar.gz