Bump numpydoc from 1.4.0 to 1.6.0 (#504)

Bumps [numpydoc](https://github.com/numpy/numpydoc) from 1.4.0 to 1.6.0.
- [Release notes](https://github.com/numpy/numpydoc/releases)
- [Changelog](https://github.com/numpy/numpydoc/blob/main/doc/release_notes.rst)
- [Commits](numpy/numpydoc@v1.4.0...v1.6.0)

---
updated-dependencies:
- dependency-name: numpydoc
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Paul Profizi <100710998+PProfizi@users.noreply.github.com>

requirements/requirements_docs.txt

@@ -1,6 +1,6 @@
 pypandoc==1.10
 imageio==2.31.3
-numpydoc==1.4.0
+numpydoc==1.6.0
 imageio-ffmpeg==0.4.7
 Sphinx<7.2.0; python_version == '3.8'
 Sphinx==7.2.5; python_version >= '3.9'