ci: add workflow to check Go versions of dependencies

[DmitriyLewen]

Description

Starting from Go 1.21, it checks the go line in all dependencies of go.mod, and determines the minimum Go version.
See #5323 (comment).

Before Go 1.22 is released - Create GitHub action to find dependencies that require Go 1.21 to avoid incorrect updates.

Test Runs:

• github.com/sigstore/rekor v1.2.2 - https://github.com/DmitriyLewen/trivy/actions/runs/6417364208/job/17422935840
• github.com/sigstore/rekor v1.3.0 - https://github.com/DmitriyLewen/trivy/actions/runs/6417443453/job/17423186672?pr=16#step:4:483

Related issues

• build: fix a compile error with Go 1.21 #5338

Checklist

• I've read the guidelines for contributing to this repository.
• I've followed the conventions in the PR title.
• 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).

[knqyf263]

Can we add a comment that it is a workaround until oldstable will be Go 1.21? I don't think this problem will occur with oldstable: Go 1.21 and stable: 1.22.

[DmitriyLewen]

Done