Feature: add e2e tests

[laurentsimon]

We need e2e tests. We will need to create test repos that generate provenance and verify via schedule events; and report an issue automatically if they fail

[laurentsimon]

We also need adversarial tests that try to alter data in the artifact registry the builder uses to pass data between jobs

[laurentsimon]

List:

• Different triggers (push, workflow_dispatch, schedule, new-tag)
• Different branches (for each trigger above)
• Setup pre-submit e2e tests to the extent that it is possible
• Adversarial tests where the caller workflow manipulate the artifacts
• Adversarial tests with an invalid input file name
• Workflow input arguments (upload-assets)
• Different arguments: vary the env variables, make sure the final provenance contains the right information
• Different config files: make sure the final provenance contains the right information. Remaining: e2e tests for Feature: add support for dir: field of goreleaser slsa-github-generator-go#128
• Builder information, such as runner env (except hash)
• Auto-close issues when e2e tests pass
• Document how it works and what each workflow does
• compile-builder option Reduce action runtime #74
• adversarial test with bogus binary in releases

[laurentsimon]

We should verify that the the provenance generated by these e2e tests can be verified by the slsa-verifier at head and for previous versions released

[laurentsimon]

Done. Closing.