build(deps-dev): bump types-markdown

Bumps [types-markdown](https://github.com/python/typeshed) from 3.10.2.20260518 to 3.10.2.20260712.
- [Commits](https://github.com/python/typeshed/commits)

---
updated-dependencies:
- dependency-name: types-markdown
  dependency-version: 3.10.2.20260712
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pyproject.toml

@@ -68,7 +68,7 @@ dev-mkdocs = [
 ]
 dev-mypy = [
   "mypy == 2.3.0",
-  "types-Markdown == 3.10.2.20260518",
+  "types-Markdown == 3.10.2.20260712",
   # For checking the noxfile, docs/ script, and tests
   "frequenz-core[dev-mkdocs,dev-noxfile,dev-pytest]",
 ]