[CLC] Update on maintenance status

As part of an attempt to create an [inventory of core libraries and their maintenance status](https://github.com/haskell/core-libraries-committee/issues/355), I'm contacting every core library that neither had a hackage upload, nor a git commit **in the last 6 months**.

If you're still active, please feel free to close this ticket and potentially give us an updated list of maintainers.

If you need assistance with maintenance, we're able to assist as well.