bump golang to 1.21.3

[MinerYang]

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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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"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

Merging #19504 (af03dda) into main (064a109) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main   #19504   +/-   ##
=======================================
  Coverage   67.44%   67.44%           
=======================================
  Files         989      989           
  Lines      108836   108836           
  Branches     2752     2752           
=======================================
+ Hits        73403    73407    +4     
+ Misses      31471    31467    -4     
  Partials     3962     3962           

Flag	Coverage Δ
unittests	67.44% <ø> (+<0.01%)	⬆️

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see 6 files with indirect coverage changes