Add doc changes after rc1 to v1.12 docs

[allenxu404]

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[allenxu404]

/kind changelog-not-required

[codecov]

Codecov Report

Merging #6812 (0a0702d) into main (9b1cffc) will decrease coverage by 0.04%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #6812      +/-   ##
==========================================
- Coverage   60.46%   60.43%   -0.04%     
==========================================
  Files         242      242              
  Lines       26038    26038              
==========================================
- Hits        15745    15737       -8     
- Misses       9187     9194       +7     
- Partials     1106     1107       +1     

see 1 file with indirect coverage changes