Update Connection reference counting to use ref counting APIs

[anrossi]

Description

Update QUIC_CONNECTION RefCount to use CXPLAT_REF_COUNT and also update the detailed ref counts to use the CXPLAT_REF_COUNT type. Related to #5570

Testing

CI

Documentation

N/A

[codecov]

Codecov Report

❌ Patch coverage is 76.19048% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 85.09%. Comparing base (0993493) to head (999a3b8).
⚠️ Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
src/core/connection.h	68.75%	5 Missing ⚠️

❌ Your patch check has failed because the patch coverage (76.19%) is below the target coverage (80.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5584      +/-   ##
==========================================
+ Coverage   84.85%   85.09%   +0.23%     
==========================================
  Files          60       60              
  Lines       18639    18657      +18     
==========================================
+ Hits        15816    15876      +60     
+ Misses       2823     2781      -42     

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