Install pelican dependencies in final stage container

[jhiemstrawisc]

We've run into a lot of issues with the way we install dependencies in our production container, including the inability to determine versions for what's installed, and shared objects that are copied without bringing along their dependencies.

Instead, we should just install whatever we can directly as an RPM into the final-stage container. This solves both issues in one fell swoop of a Pelican's beak.

[jhiemstrawisc]

This also partially addresses some of the concerns raised in #1866.

[brianaydemir]

LGTM.

[brianaydemir]

Brief overview of my testing:

1. Check out the PR locally.

2. docker build --target final-stage -t pelican:latest -f images/Dockerfile .

3. Start my bespoke Docker Compose setup using this image.

4. In the dev environment container, run pelican serve --module director,registry,origin,cache --config config.yaml.

5. Log into the Web UI, select the registry, and accept all the pending registrations.

6. In the user environment container:

   • Try an object ls.
   • Try an object get as a direct read.
   • Try an object get via the cache, using -c. (Cache miss.)
   • Try the same exact thing. (Cache hit.)
   • Try an object get.
   • Try an object put. (Requires a token.)

Files:

• docker-compose.txt
• config.txt