ci: fix skopeo running errors

[zyy17]

I hereby agree to the terms of the GreptimeDB CLA

What's changed and what's your intention?

Fix skopeo running errors:

• Use env to inject credentials;

• Use skopeo latest stable container instead of installing from apt;

Please explain IN DETAIL what the changes are in this PR and why they are needed:

• Summarize your change (mandatory)
• How does this PR work? Need a brief introduction for the changed logic (optional)
• Describe clearly one logical change and avoid lazy messages (optional)
• Describe any limitations of the current code (optional)

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.

Refer to a related PR or issue link (optional)

[codecov]

Codecov Report

Merging #2581 (262c25c) into develop (0a9972a) will decrease coverage by 0.37%.
The diff coverage is n/a.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #2581      +/-   ##
===========================================
- Coverage    85.35%   84.99%   -0.37%     
===========================================
  Files          737      737              
  Lines       118020   118020              
===========================================
- Hits        100735   100306     -429     
- Misses       17285    17714     +429