Update myst-parser requirement from ~=3.0 to ~=4.0

Updates the requirements on [myst-parser](https://github.com/executablebooks/MyST-Parser) to permit the latest version.
- [Release notes](https://github.com/executablebooks/MyST-Parser/releases)
- [Changelog](https://github.com/executablebooks/MyST-Parser/blob/master/CHANGELOG.md)
- [Commits](executablebooks/MyST-Parser@v3.0.0...v4.0.0)

---
updated-dependencies:
- dependency-name: myst-parser
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

docs/doc_requires.txt

@@ -3,7 +3,7 @@ nbsphinx~=0.9
 pygments~=2.18
 shibuya~=2024.7
 ipykernel~=6.29
-myst_parser~=3.0  # Must Be Underscore, not Hyphen
+myst_parser~=4.0  # Must Be Underscore, not Hyphen
 sphinx-intl~=2.2
 sphinx_favicon~=1.0
 sphinx-copybutton~=0.5