tests/validate_yaml: add validation for KCIDB mapping

[JenySadadia]

To submit KernelCI generated data to KCIDB, it is required to have a mapping for all the job definitions with kcidb_test_suite property. Add validation to ensure all the jobs have a mapping present to avoid missing data submission. This check is to notify test authors trying to enable tests in maestro to include the required property for the mapping in their definition.

[nuclearcat]

I think it is good if i merge it asap, so it will validate current config updates. Thank you!

[JenySadadia]

LGTM

These checks could also be added to kci config validate tool (which checks section order) but that's a future task

Yes, that's a good idea.