Bump ipywidgets from 8.0.7 to 8.1.0 (zarr-developers#1510)

Bumps [ipywidgets](https://github.com/jupyter-widgets/ipywidgets) from 8.0.7 to 8.1.0.
- [Release notes](https://github.com/jupyter-widgets/ipywidgets/releases)
- [Commits](jupyter-widgets/ipywidgets@8.0.7...8.1.0)

---
updated-dependencies:
- dependency-name: ipywidgets
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements_dev_optional.txt

@@ -3,7 +3,7 @@
 lmdb==1.4.1; sys_platform != 'win32'
 # optional library requirements for Jupyter
 ipytree==0.2.2
-ipywidgets==8.0.7
+ipywidgets==8.1.0
 # optional library requirements for services
 # don't let pyup change pinning for azure-storage-blob, need to pin to older
 # version to get compatibility with azure storage emulator on appveyor (FIXME)