The original logic is if the given test targets do not start with
`//tests:`, then add this prefix for them.

I'm removing this logic as:
1. We don't actually see any use cases in the workflow
2. It will block us running per-directory suite targets such as
`//tests/mosaic:gpu_tests`

Signed-off-by: ashors1 <[email protected]>

- Increase timeout as A100 tests take >1 hour to run
- Report the test failures/errors, not collection failures/errors