feat: support concurrency queue and job.workflow_* contexts

[leno23]

Summary

Fixes #657 and #647.

• Parse queue in workflow and job concurrency sections
• Validate job.workflow_ref, job.workflow_sha, job.workflow_repository, and job.workflow_file_path in expressions

Test plan

• go test ./...

[muzimuzhi]

• Parse queue in workflow and job concurrency sections

PR #654 also addresses this part.