Hello @Arsi,
normally it is "safe" to proceed if only this one fails. Meaning, deployment tester is exactly that, a tester unit. Not the operational.
I always recommend to run with as less errors as possible. And in some flavours of organizations, errors are not very well seen, at all, not allowed.
If you go for solving the problem, I would check the logs in depth. Did you configured JUnit in the process, and on the right version?