Find a maintainer or update support condition

### Before submitting an issue, please be sure to

- [x] Read [the contributing instructions](https://github.com/github/pages-gem/blob/master/docs/CONTRIBUTING.md#contributing-to-the-github-pages-gem)
- [x] Update to the latest Gem version (run `bundle update github-pages`)

### This issue affects

- [x] The site generated by GitHub Pages
- [x] Building sites locally

*The GitHub Pages Gem is intended to help users replicate the GitHub Pages build environment locally. If your issue affects both the hosted version and the version previewed locally, you may be better suited reporting [seeking support in other forums](https://github.com/github/pages-gem/blob/master/docs/SUPPORT.md).*

### What did you do (e.g., steps to reproduce)

I watched this repository and related Jekyll GitHub Pages repositories begin to look like abandoned-ware.

### What did you expect to happen?

I expected somebody with authority in the project to maintain the code, respond to potential contributors, and to handle security issues identified with its dependencies. I expect GitHub to maintain and improve the system it created.

### What happened instead?

I saw the project slowly increase in the number of unhandled and unacknowledged issues, pull requests, and security findings.

### Additional information

* Link to the live site (if applicable): n/a
* Link to the source repo (if applicable): n/a

Start by reviewing the issue's concerns alongside docs/CONTRIBUTING.md and docs/SUPPORT.md, which are linked in the report. Done would require a decided maintenance or support direction, such as an identified maintainer or an updated support condition; the issue does not define a specific code change or test.

Written by the indexing model from the issue text.