Change the copy to use `ActionsArtifact.StoragePath` instead of the
`ArtifactPath`. Skip artifacts that are expired, and don't error if the
file to copy does not exist.
---
When trying to migrate actions artifact storage from local to MinIO, we
encountered errors that prevented the process from completing
successfully:
* The migration tries to copy the files using the per-run
`ArtifactPath`, instead of the unique `StoragePath`.
* Artifacts that have been marked expired and had their files deleted
would throw an error
* Artifacts that are pending, but don't have a file uploaded yet will
throw an error.
This PR addresses these cases, and allow the process to complete
successfully.
(cherry picked from commit 8de8972baf5d82ff7b58ed77d78e8e1869e64eb5)
(cherry picked from commit 4afbfd3946)
Rowan Bohde