feat(rulesets): add rule to check if messageId is defined

[magicmatatjahu]

Checklist

• [X] Tests added / updated
• [X] Docs added / updated

Does this PR introduce a breaking change?

• [ ] Yes
• [X] No

Additional context

• change severity of asyncapi-operation-operationId rule from error to warning
• add asyncapi-message-messageId rule, with similar functionality like asyncapi-operation-operationId
• add unit tests
• update docs
• add more formats (needed by new rule)
• merge traits before checking ids.

cc @jonaslagoni @smoya

[magicmatatjahu]

I have to update that PR to handle also cases with traits. For messageId and operationId.

[P0lip]

Yeah, I'd say it's a breaking change indeed. As such, we could release spectral-rulesets 2.x.x if you're okay with. I don't have any issue with it.

[magicmatatjahu]

@smoya @P0lip I'm not a fan to release version 2.0.0 rulesets with such a case. As there will be much bigger changes then we will change error to warning, now I reverted my changes regarding operationId. Please check again, thanks!