Add go clean in Dockerfile and action.

[blackpiglet]

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Please add a summary of your change

This PR is used to resolve the push Github action's failure. The failure is caused by no space left on the disk.
This PR adds go clean after the local build and the docker image build.

Does your change fix a particular issue?

Fixes #(issue)

Please indicate you've done the following:

• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• Updated the corresponding documentation in site/content/docs/main.

[codecov]

Codecov Report

Merging #6895 (64595cc) into main (c619179) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #6895   +/-   ##
=======================================
  Coverage   60.76%   60.76%           
=======================================
  Files         247      247           
  Lines       26322    26322           
=======================================
  Hits        15995    15995           
  Misses       9190     9190           
  Partials     1137     1137