Build(deps-dev): Bump the development-dependencies group with 4 updates (#41599)

- @astrojs/markdown-remark: ^6.3.2  →    ^6.3.3
- @astrojs/mdx: ^4.3.0  →    ^4.3.1
- astro: ^5.11.1  →   ^5.12.0
- stylelint: ^16.21.1  →  ^16.22.0

Author: julien-deramond