chore: pin GitHub Actions workflows to full commit SHAs

[irfanuddinahmad]

Pins all uses: action refs to their full commit SHA with the version tag preserved as a comment. Part of org-wide SHA-pinning migration: openedx/.github#165

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.26%. Comparing base (ed2bb54) to head (77f7c9c).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2403   +/-   ##
=======================================
  Coverage   95.26%   95.26%           
=======================================
  Files         196      196           
  Lines       21679    21679           
  Branches     1509     1509           
=======================================
  Hits        20653    20653           
  Misses        776      776           
  Partials      250      250           

Flag	Coverage Δ
unittests	95.26% <ø> (ø)

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[pomegranited]

👍

• I tested this green CI is sufficient
• I have bumped this package's version
• I read through the code and checked the code hashes used match the tagged versions they replace.