chore(doc): Reformat readme tags

[itayporezky]

(Draft, see open questions below)

Background:

After using the docker agents for much time, i found i was actually using less optimal tags then the ones i randomly discovered in the dockerhub tag search

Description

1. This is a reformatting of the readme to hopefully make the tags that are available to be used more clear.
2. Also added 1 more tag in the bake file to align with the same amount of tags created on alpine and same format.
3. Open questions:

• which i thought about too late: Is there an actual need for so many JDK flavors?
• Deprecate archlinux? released tags seem old

(I suggest to review using some Markdown previewer)
Related #777

Testing done

N/A

Submitter checklist

Beta Give feedback

1. Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
2. Ensure that the pull request title represents the desired changelog entry
3. Please describe what you did
4. Link to relevant issues in GitHub or Jira
5. Link to relevant pull requests, esp. upstream and downstream changes
6. Ensure you have provided tests - that demonstrates feature works or fixes the issue

[timja]

I've pushed some general improvements, ideally tagged builds would be promoted in some way, they are quite far down and probably not as clear as they should be but I think this is better than before so approving.

[timja]

Deprecate archlinux? released tags seem old

See #422

[itayporezky]

Looks good for now :)

[timja]

FWIW in case you are interested, inbound agent is in an even worse state with no mentioned tags
https://github.com/jenkinsci/docker-agent/blob/master/README_inbound-agent.md

https://hub.docker.com/r/jenkins/inbound-agent