feat(GCS+gRPC): implement PatchDefaultObjectAcl()

[coryan]

Fixes #4181

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[codecov]

Codecov Report

Merging #9487 (60354fb) into main (60354fb) will not change coverage.
The diff coverage is n/a.

❗ Current head 60354fb differs from pull request most recent head 02b500c. Consider uploading reports for the commit 02b500c to get more accurate results

@@           Coverage Diff           @@
##             main    #9487   +/-   ##
=======================================
  Coverage   94.64%   94.64%           
=======================================
  Files        1485     1485           
  Lines      137036   137036           
=======================================
  Hits       129695   129695           
  Misses       7341     7341           

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[coryan]

/gcbrun

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