Bump myst-parser in /{{cookiecutter.project_slug}}/docs

Bumps [myst-parser](https://github.com/executablebooks/MyST-Parser) from 0.18.1 to 0.19.0.
- [Release notes](https://github.com/executablebooks/MyST-Parser/releases)
- [Changelog](https://github.com/executablebooks/MyST-Parser/blob/master/CHANGELOG.md)
- [Commits](executablebooks/MyST-Parser@v0.18.1...v0.19.0)

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

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

{{cookiecutter.project_slug}}/docs/requirements.txt

@@ -3,7 +3,7 @@ poetry==1.4.0
 # Documentation building
 emoji==2.2.0
 importlib-metadata==6.0.0
-myst-parser==0.18.1
+myst-parser==0.19.0
 pygments==2.14.0
 sphinx==5.3.0
 sphinx-autoapi==2.0.1