v1.17: ci: add the ability to use GCS backend for sccache (backport of #33967)

[mergify]

This is an automatic backport of pull request #33967 done by Mergify.

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[codecov]

Codecov Report

Merging #33984 (9779588) into v1.17 (9779588) will not change coverage.
Report is 4 commits behind head on v1.17.
The diff coverage is n/a.

❗ Current head 9779588 differs from pull request most recent head 8dfd59a. Consider uploading reports for the commit 8dfd59a to get more accurate results

@@           Coverage Diff           @@
##            v1.17   #33984   +/-   ##
=======================================
  Coverage    81.8%    81.8%           
=======================================
  Files         803      803           
  Lines      217864   217864           
=======================================
  Hits       178337   178337           
  Misses      39527    39527