bump golang to 1.21.3 on release-2.9.0

[MinerYang]

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Comprehensive Summary of your change

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• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
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[codecov]

Codecov Report

Merging #19503 (b174938) into release-2.9.0 (4f77fbe) will decrease coverage by 3.20%.
Report is 1 commits behind head on release-2.9.0.
The diff coverage is n/a.

❗ Current head b174938 differs from pull request most recent head be1595d. Consider uploading reports for the commit be1595d to get more accurate results

@@                Coverage Diff                @@
##           release-2.9.0   #19503      +/-   ##
=================================================
- Coverage          70.60%   67.40%   -3.20%     
=================================================
  Files                749      993     +244     
  Lines              95516   108932   +13416     
  Branches               0     2752    +2752     
=================================================
+ Hits               67435    73426    +5991     
- Misses             24432    31552    +7120     
- Partials            3649     3954     +305     

Flag	Coverage Δ
unittests	67.40% <ø> (-3.20%)	⬇️

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see 250 files with indirect coverage changes