SLK-87780 | Fix failed sent email when app scope owner is empty

[haiataquasec]

This ticket aims to fix:

1. Correct expected format of email
2. Disregard empty string in case server sent (should not happen but you never know)
3. Use panic recovery in any case of panic error. Though that piece of code should continue the loop and send other emails present in job, it does not perform as expected so I added it just in case.

Related PR in Server: https://bitbucket.org/scalock/server/pull-requests/28142

Resolves: SLK-87780

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