Fix broken JFrog CLI Plugins docs links in README

[Balasubramanyamkosuri]

Summary

• Update the broken JFrog CLI Plugins README links that pointed at unavailable docs.jfrog-applications.jfrog.io URLs.
• Plugins docs now point to https://docs.jfrog.com/integrations/docs/jfrog-cli-plugins.
• Plugin Developer Guide now points to the in-repo guide: guides/jfrog-cli-plugins-developer-guide.md.

Test plan

• Open https://github.com/jfrog/jfrog-cli#jfrog-cli-plugins and confirm both plugins section links resolve correctly

[github-actions]

All contributors have signed the CLA ✍️ ✅
_{Posted by the CLA Assistant Lite bot.}

[Balasubramanyamkosuri]

I have read the CLA Document and I hereby sign the CLA

[Balasubramanyamkosuri]

recheck

[Balasubramanyamkosuri]

@bhanurp Could you please review and approve this PR when you get a chance? CI is green; it only updates the broken JFrog CLI Plugins docs links in the README.

[Balasubramanyamkosuri]

@bhanurp Thanks for the code review approval!

Could you also approve the waiting build-gate deployment so the remaining CI can run, and then merge when green?

Approve here: https://github.com/jfrog/jfrog-cli/actions/runs/29330273605 → Approve and deploy

PR: #3600

[Balasubramanyamkosuri]

@bhanurp Thanks for the code review approval!

Could you also approve the waiting build-gate deployment so the remaining CI can run, and then merge when green?

Approve here: https://github.com/jfrog/jfrog-cli/actions/runs/29330273605 → Approve and deploy

I can’t do this myself — the build-gate environment requires approval from a maintainer team (ecosystem / ecomatrix / related), and as a fork contributor I don’t have permission to approve that deployment or merge into jfrog/jfrog-cli.

PR: #3600

[Balasubramanyamkosuri]

@bhanurp Thanks for the PR review approval!

What’s still pending is the separate Actions build-gate deployment (not the PR review button). Could you please open this run and click Approve and deploy?

https://github.com/jfrog/jfrog-cli/actions/runs/29330273605

Once that is approved, the remaining CI suites can run and the PR can be merged when green.