[bodiam]

What kind of change does this PR introduce?

• Add a project
• Update a project
• Remove a project
• Add or update a category
• Change configuration
• Documentation
• Other, please describe:

Description:

Adds mkdocs-allscreenshots-og-screenshot, a MkDocs plugin that adds a per-page og:image meta tag pointing at a live screenshot of the page, rendered via the Allscreenshots API.

• PyPI: https://pypi.org/project/mkdocs-allscreenshots-og-screenshot/ (0.1.2, MIT)
• GitHub: https://github.com/allscreenshots/mkdocs-og-image-plugin (MIT)
• Entry point: allscreenshots-og-screenshot (mkdocs.plugins)
• Category: html-css

Disclosure: I'm the author and maintainer of this plugin and owner of allscreenshots.com. I searched projects.yaml, the README, and open/closed issues and PRs and found no existing entry or suggestion for it.

Checklist:

• I have read the CONTRIBUTING guidelines.
• I have not modified the README.md file. Projects are only supposed to be added or updated within the projects.yaml file since the README.md file is automatically generated.