chore: use mirror.gcr.io for trivy-check by default

[afdesk]

Description

This PR adds mirror.gcr.io as a source for trivy-checks by default.

Checklist

• [x] I've read the guidelines for contributing to this repository.
• [ ] I've added tests that prove my fix is effective or that my feature works.
• [ ] I've updated the documentation with the relevant information (if needed).
• [ ] I've added usage information (if the PR introduces new options)
• [ ] I've included a "before" and "after" example to the description (if the PR is a user interface change).