chore(deps): update dependency nbsphinx to v0.9.6 (#947)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [nbsphinx](https://nbsphinx.readthedocs.io/) | `==0.9.5` -> `==0.9.6`
|
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|
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|
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|
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|

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docs/requirements.txt

@@ -1,7 +1,7 @@
 myst-parser==4.0.0
 rstcheck==6.2.4
 sphinx==8.1.3
-nbsphinx==0.9.5
+nbsphinx==0.9.6
 sphinx-autobuild==2024.10.3
 sphinx-markdown-parser==0.2.4
 sphinxcontrib-actdiag==3.0.0