Document plugin release plans as part of roadmap/milestone #6629

[kaovilai]

Signed-off-by: Tiger Kaovilai tkaovila@redhat.com

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Does your change fix a particular issue?

Fixes #6629

Please indicate you've done the following:

• [x] Accepted the DCO. Commits without the DCO will delay acceptance.
• [x] Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• [x] Updated the corresponding documentation in site/content/docs/main.

/kind changelog-not-required

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 58.42%. Comparing base (facfb95) to head (aa494e8).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #7686 +/- ## ========================================== + Coverage 58.15% 58.42% +0.27% ========================================== Files 343 343 Lines 35770 28394 -7376 ========================================== - Hits 20801 16590 -4211 + Misses 13552 10387 -3165 Partials 1417 1417 ```

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