This creates a reusable workflow that automatically attest a GitHub release based on its content. It's possible to also pass additional materials to be added to the attestation. Additionally it will try to create a workflow if it does not exist.

By default it will attest:

• All assets within a GitHub Release
• The source code in a .tar.gz

Required parameters:

• API Token: Chainloop API token to perform the attestation
• Cosign key and password: To sign the final attestation
  Optional parameters:
• Workflow name: Name of the target workflow to be attested
• Project: Name of the project
• Additional materials: Comma separated list of values to be added to the attestation

Closes chainloop-dev/chainloop#844