review --graceful-exit default behavior

[migmartri]

The chainloop attestation CLI has an optional behavior called enabled via --graceful-exit that makes the CLI not fail

In those cases, we might still want to know that the command failed. So this task is about

• [ ] review what's the current behavior of this flag
• [ ] look into supporting the report of an error without failing

Note that this task might not end up with an implementation but instead with some documentation. For example, we might end up documenting how to achieve the second goal with hash in a runbook page.