feat: support slsa-verifier's -build-workflow-input

[suzuki-shunsuke]

Close #3613

• Support slsa-verifier's --build-workflow-input
• Support disabling slsa-verifier's --source-tag

slsa_provenance:
  type: github_release
  asset: multiple.intoto.jsonl
  inputs:
    

[suzuki-shunsuke]

⚠️ Blocker

Probably we want to use template variables in input variables.
But the needs is not clear.
We shouldn't implement the feature until the needs becomes clear.