build(deps): update nbsphinx requirement from <=0.9.2,>=0.8.5 to >=0.8.5,<=0.9.7 in /requirements (#20815)

build(deps): update nbsphinx requirement in /requirements

Updates the requirements on [nbsphinx](https://github.com/spatialaudio/nbsphinx) to permit the latest version.
- [Release notes](https://github.com/spatialaudio/nbsphinx/releases)
- [Changelog](https://github.com/spatialaudio/nbsphinx/blob/master/NEWS.rst)
- [Commits](spatialaudio/nbsphinx@0.8.5...0.9.7)

---
updated-dependencies:
- dependency-name: nbsphinx
  dependency-version: 0.9.7
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements/docs.txt

@@ -1,6 +1,6 @@
 sphinx >5.0, <6.0
 myst-parser >=0.18.1, <3.0.0
-nbsphinx >=0.8.5, <=0.9.2
+nbsphinx >=0.8.5, <=0.9.7
 nbconvert <7.14  # temporary fix for https://github.com/jupyter/nbconvert/issues/2092
 pandoc >=1.0, <=2.3
 docutils >=0.16, <0.22