Roles: Audit all existing titles and membership

Motivation: Over the years, the Project has evolved more quickly than `roles.json` (that renders to https://www.astropy.org/team) can be updated. As a result, there are now roles that do not exist anymore (or inactive) and people who do not really fill existing roles anymore. I would like to submit a series of PRs to update this listing, or at least put the roles in discussion.

Depends on:

* Developer survey results (2023 and maybe also 2022) -- who replied and who MIA?
* Community discussions (on this issue, on related PRs, mailing lists, Slack, etc)

Also might be relevant:

* #167
* https://github.com/astropy/astropy-project/issues/358

Existing roles (as of 2023-03-06):

- [x] Coordination committee member -- This is decided by election. No further action needed.
- [x] Ombudsperson -- Still true. No further action needed.
- [ ] Community engagement coordinator -- Do we really need so many sub-roles? Can this be all merged into one when we hire a proper community manager? #524 #597
- [x] Astropy GSoC coordinator -- #518
- [ ] Learn Team -- Do we really need so many sub-roles? Are these even still active? Can this be simplified? #525 and https://github.com/astropy/astropy-project/issues/354
- [x] Finance committee member -- This committee is active. No further action needed except https://github.com/astropy/astropy.github.com/pull/535
- [ ] Documentation infrastructure maintainer -- Can this be merged with "Testing infrastructure maintainer"? I am active in both and they do overlap a lot. #520 https://github.com/astropy/astropy.github.com/pull/613
- [x] Affiliated package review editor -- They are active. No further action needed.
- [x] Astropy.org web page maintainer -- ~I don't know what this means. If this is simply who holds the DNS account, I think this is overkill and can be removed. If not, please clarify what this role actually does. If this includes `sites.json`, then Moritz should be on there.~ #545
- [x] Astropy-helpers maintainer -- #517
- [ ] DevOps and Operations Specialist -- We tried to hire an official person to do this but that person is no longer active and the position has lapsed. I say we remove this because this is now split into other roles already mentioned (e.g., infrastrucure, core). #522 #539 #596 https://github.com/astropy/astropy.github.com/pull/613
- [ ] Testing infrastructure maintainer -- Can this be merged with "Documentation infrastructure maintainer"? I am active in both and they do overlap a lot. #520 https://github.com/astropy/astropy.github.com/pull/613
- [x] Package template maintainer -- We plan to retire the template in favor of OpenAstronomy's, so we should remove this role because it is no longer actively maintained. See https://github.com/astropy/package-template/issues/519 . #523
- [x] CI-helpers maintainer -- #517
- [ ] Distribution coordinator -- It is very hard to vet this one since distro activities happen outside the purview of Astropy. I know some of these people are active while hardly heard from the other ones, though that does not mean they are not doing anything either. Also, other distros out there might be distributing `astropy` also but we don't list them. Ideas welcome.
- [ ] Dev-telecon coordinator -- Moritz has been hosting the last few by himself. Is this role really working out or do we need something else? Is it overkill to have a named role just for this telecon? #598
- [x] Release team -- I only am aware of Tom R and Simon C who are actively doing core releases. I vote to remove the inactive ones. See https://github.com/astropy/astropy.github.com/pull/530
- [ ] Core astropy package maintainer (general) -- This one is relative new. Both Derek and I are active. I guess no further action needed? Any action here also affects #522
- [x] Subpackage: `constants` -- This is low-activity and looks about right. No further action needed.
- [ ] Subpackage: `convolution` -- Is Axel still active? Need to find out.
- [ ] Subpackage: `coordinates` -- So many maintainers, truly? Need to double check. https://github.com/astropy/astropy.github.com/pull/603
- [x] Subpackage: `cosmology` -- Single point of failure though maintainer is active. Looks about right. 😆 No further action needed.
- [x] Subpackage: `io.ascii` -- Looks about right. No further action needed.
- [x] Subpackage: `io.fits` -- Single point of failure though maintainer is active. Looks about right. 😆 No further action needed.
- [ ] Subpackage: `io.misc` -- https://github.com/astropy/astropy.github.com/pull/612
- [ ] Subpackage: `io.votable` -- Have not seen Boch in a while. Need to find out.
- [x] Subpackage: `modeling` -- Looks about right. No further action needed.
- [x] Subpackage: `nddata` -- Matt is still stuck with it but has a plan that is out of scope here. No further action needed.
- [x] Subpackage: `samp` -- Yup, no one. Someday maybe https://github.com/astropy/pyvo/issues/155
- [x] Subpackage: `stats` -- Single point of failure though maintainer is active. Looks about right. 😆 No further action needed.
- [x] Subpackage: `table` -- Looks about right. No further action needed.
- [x] Subpackage: `time` -- Looks about right. No further action needed.
- [ ] Subpackage: `timeseries` -- Have not seen a lot of activities here. Need to double check.
- [ ] Subpackage: `uncertainties` -- Have not seen a lot of activities here. Need to double check.
- [x] Subpackage: `units` -- Looks about right. No further action needed.
- [ ] Subpackage: `utils` -- I think this is mostly Marten and I nowadays. Need to double check. https://github.com/astropy/astropy.github.com/pull/603
- [x] Subpackage: `visualization` -- Looks about right. No further action needed.
- [x] Subpackage: `wcs` -- Looks about right. No further action needed.
- [x] Coordinated: `astroquery` -- Is Clara still active? Need to double check.
- [x] Coordinated: `astropy-healpix` -- This is low-activity and looks about right. No further action needed.
- [x] Coordinated: `photutils` -- Need to double check. #599
- [x] Coordinated: `ccdproc` -- Is Matt still developing it? Need to double check.
- [x] Coordinated: `specutils` -- Some names are no longer active there. Need to double check. #548 #601
- [x] Coordinated: `reproject` -- Is Stuart still involved? Need to double check.
- [x] Coordinated: `regions` -- Looks about right. No further action needed.
- [x] Coordinated: `asdf-astropy` -- Looks about right. No further action needed.
- [x] Coordinated: `specreduce` -- This entry is completely missing. We need to add this and clean up access. https://github.com/astropy/astropy.github.com/pull/521 and #547