add composer.libraries.json file

We appreciated your useful contribution. This sounds better than the linked issue, technically.

We should close the other issue even if this one is a dup due to no progress in there.

The only objections I mentioned anywhere so far in those dups are:

1. Accessible Slick vs. regular Slick vs. working versions.
2. It will open up security issues in this module. A very low quality of security issues that only add unnecessary noises.

   We didn't want this module or any I maintained to be a snack for script kiddies. Real Drupal developers are not script kiddies, of course, but they are just anywhere I know some of for sure.

   It is public knowledge that third party libraries may contain security holes. Even if you think such a hole is no longer relevant now, Slick library v1 did have it.

   If you don't know such a thing, you are well informed now. I had worked with Slick since 2014 so you have an authoritative reply.

   Whenever we can, we should minimize low quality noise downstream to not leak or crop up to the serious-level upstream, even if it is indeed very useful. Shortly, usefulness must be set aside for seriousness.

Anyway as I said in the linked issue, due to dups, if you or anyone can elaborate and convince me about those three issues, I am all ears.

Thank you.

Note:
Intentionally postponed due to too many dups. Feel free to re-open you can address the above mentioned issues without being offhanded.

3.x is out.

Any contribution should refer to the provided docs as outlined at project home:
https://git.drupalcode.org/project/slick/-/blob/3.0.x/docs/CONTRIBUTION....

Changing target branch.

Reverting. I don't know how to update a merge request to target a different branch properly.