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

[kaovilai]

Signed-off-by: Tiger Kaovilai [email protected]

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Does your change fix a particular issue?

Fixes #6629

Please indicate you've done the following:

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

/kind changelog-not-required

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

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

Additional details and impacted files

@@            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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