[deps] Update responses requirement from ~=0.26.0 to ~=0.26.1

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@0.26.0...0.26.1)

---
updated-dependencies:
- dependency-name: responses
  dependency-version: 0.26.1
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements-test.txt

@@ -1,3 +1,3 @@
 pytest-cov~=7.1.0
-responses~=0.26.0
+responses~=0.26.1
 openwisp-utils[qa,selenium,channels,channels-test] @ https://github.com/openwisp/openwisp-utils/archive/refs/heads/1.3.tar.gz