fix: #8014
> ERROR: Invalid experiment '{entry.stash_rev[:7]}'.
This happens when the queue task failed from a scm error.
{"exc_type": "GitMergeError", "exc_message": ["Cannot fast-forward HEAD
to '05100047a341f2fa4a02421289d48f84d8c45e86'"], "exc_module": "dvc.scm"}.
And the failed task neither create a infofile nor create a fail_stash.
1. Didn't raise DvcException if no infofile found for failed tasks.
(success tasks still raise it)
2. Add a new unit test for this.
karajan1001
306456d453