[release/10.0] Update NuGet packaging version to 6.12.5

[github-actions]

Backport of #14665 to release/10.0

/cc @LeafShi1 @Shyam-Gupta

Customer Impact

Testing

Risk

Microsoft Reviewers: Open in CodeFlow

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 77.10775%. Comparing base (2d61273) to head (454aa5e).

Additional details and impacted files

@@                  Coverage Diff                   @@
##           release/10.0      #14822         +/-   ##
======================================================
- Coverage      77.10915%   77.10775%   -0.00141%     
======================================================
  Files              3273        3273                 
  Lines            645083      645083                 
  Branches          47708       47708                 
======================================================
- Hits             497418      497409          -9     
  Misses           143989      143989                 
- Partials           3676        3685          +9     

Flag	Coverage Δ
Debug	77.10775% <ø> (-0.00141%)	⬇️
integration	18.98188% <ø> (-0.00558%)	⬇️
production	51.92827% <ø> (-0.00313%)	⬇️
test	97.40991% <ø> (ø)
unit	49.34625% <ø> (+0.00069%)	⬆️

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