Bump ipywidgets from 8.1.0 to 8.1.1 in /extra_requirements

Bumps [ipywidgets](https://github.com/jupyter-widgets/ipywidgets) from 8.1.0 to 8.1.1.
- [Release notes](https://github.com/jupyter-widgets/ipywidgets/releases)
- [Commits](jupyter-widgets/ipywidgets@8.1.0...8.1.1)

---
updated-dependencies:
- dependency-name: ipywidgets
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

extra_requirements/requirements-tests.txt

@@ -5,7 +5,7 @@ coveralls==3.3.1
 galpy==1.8.3
 gitpython==3.1.40
 latex==0.7.0
-ipywidgets==8.1.0
+ipywidgets==8.1.1
 matplotlib==3.5.3; python_version<='3.7'
 matplotlib==3.5.3; python_version>'3.7'
 mw_plot==0.11.0