ci: attempt to setup docker cache for etcd

[sunng87]

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What's changed and what's your intention?

Try to setup docker cache to prevent limitation of pulling etcd images.

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR does not require documentation updates.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.34%. Comparing base (06dcd0f) to head (b8e082f).
Report is 11 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3488      +/-   ##
==========================================
- Coverage   85.40%   85.34%   -0.07%     
==========================================
  Files         898      903       +5     
  Lines      148489   149657    +1168     
==========================================
+ Hits       126819   127720     +901     
- Misses      21670    21937     +267