[META] Prepare Lightning for Drupal 9

Anything that starts with lightning_*, including Lightning itself, is scanned continuously for deprecations, and tests fail if we are using deprecated code. So everything Lightning ships is D9-ready, and kept that way as a matter of course.

However, our dependencies may not be. I would suggest we file issues in each of those modules to verify their Drupal 9 readiness.

Tagging. We have a goal of making Lightning Components 100% compatible this quarter and a stretch goal for all of the dependencies.

I notice that some of the modules mentioned in the IS are core modules like file, views, block, breakpoint, etc.
Should we remove them from the IS?

Yes, please do!

Per a Slack discussion with Gábor Hojtsy regarding usage of D9 tags (Drupal 9, Drupal 9 compatibility, Drupal 9 readiness, etc.), "Drupal 9 compatibility" should be used for contributed projects that need updating and "Drupal 9" was the old tag for D8 issues before the D9 branch was ready. Doing tag cleanup here based on that discussion.

Alphabetized, deduped by project, and added some missing entries.

Fixed the issue link for Blazy.

A bunch are now done, so moving them into a DONE section.

Updated the Blazy issue link to its remaining issue.

Adding #2895377: Convert WebTestBase to BrowserTestBase as another image_widget_crop issue.

Opened #3107844: SerializableTempstoreTest calls deprecated PHPUnit methods, moving CTools back to the not-done list.

Moving lightning_api, lightning_media, and simple_gmap to done.

Moving ctools and entity_embed to Done.

Some notes from what we did:

libraries: Instead of making that work on D9, I'd focus on removing it. https://www.drupal.org/node/3099614 got in today, there's a patch already for dropzonejs and other modules should be able to be updated in the same way, you could include the core patch and already stop installing it now and recommend existing sites to uninstall.

video_embed_field and video_embed_media: Similar, we just switched to the core oembed provider, the upgrade path seems to work quite well. But likely easier for us as we control all sites and were able to write an update to migrate and uninstall, just like libraries.

Moving image_widget_crop, openapi, and schemata to DONE.

Moved information about Libraries API to its own section of the IS.

Moved a bunch of modules to DONE

Moved Panels to the "done" list.

Ditto for Panelizer.

Moving Search API to the "done" list.

Lightning 5 is released and supports Drupal 9. So this, I think, is quite fixed!