Update docformatter requirement from <1.7.5 to <1.7.6

Updates the requirements on [docformatter](https://github.com/PyCQA/docformatter) to permit the latest version.
- [Release notes](https://github.com/PyCQA/docformatter/releases)
- [Changelog](https://github.com/PyCQA/docformatter/blob/master/CHANGELOG.md)
- [Commits](PyCQA/docformatter@v0.1...v1.7.5)

---
updated-dependencies:
- dependency-name: docformatter
  dependency-type: direct:development
...

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

requirements-dev.txt

@@ -7,5 +7,5 @@ pytest-cov<=4.1.0
 freezegun<1.3.0
 pyupgrade<3.16.0
 isort<5.14.0
-docformatter<1.7.5
+docformatter<1.7.6
 bandit<1.8.0