Tidy workflows, translation strings, and remove unsused images

[hornc]

This PR:

• Prevents internetarchive project only github workflows (slack bot integrations and github issue monitoring) from running on forks
• Removes an unused support template and corresponding i18n strings: openlibrary/templates/support.html
• Removes footer link to inactive social-media
• Deletes some unused / duplicated static/images

Technical

Testing

Screenshot

Stakeholders

[mekarpeles]

tweet.svg used on footer

[hornc]

@mekarpeles This PR removes that from the footer too. The most recent posts there are 5 years or older, it doesn't appear an active relevant way to contact or interact with OL.

[mekarpeles]

@horn, our last post was mid January
https://x.com/openlibrary/status/1880031345189302753

[mekarpeles]

This would be a lot easier to review if these were submitted as individual things:

1. a workflows PR I am happy to review and these changes are useful!
2. rm unused support template + strings, also very useful PR
3. rm duplicate images also a useful PR (I'm not sure why the christianity.svg category svg was removed -- it's used on the homepage, though it can certainly be renamed).
4. there was a previous conversation around the footer where we decided to keep the existing social Update Twitter icon in the footer to the X icon #9676, Change Twitter logo to X on the home page.  #9572, Change Twitter logo to X on the home page. #9573

1 and 2 I'm happy to merge if we open PRs for them and it seems like 3 is mostly there as well.