Bug: Validation error showing up for SMART when none exists in subfeed

[evansiroky]

Describe the bug

Sonoma-Marin Area Rail Transit District August Reports site shows that there is a validation error that is causing a failed check. There is no validation error listed in the list of individual validation errors.

To Reproduce

Steps to reproduce the behavior:

1. Go to https://reports.calitp.org/gtfs_schedule/2024/08/315/
2. See failed check on no schedule validator errors, but no validator errors are individually listed

Expected behavior

Validation error should pass if there are no errors.

Additional context

Maybe the regional feed has a validation error that the reports site is finding? We shouldn't attribute errors in the regional feed to a subfeed.

[vevetron]

The first pattern I see is that the same error occurs with the MTC 511 agencies that i've checked and generally doesn't occur with other agencies.

[vevetron]

Prior work on this:
#290