BCV behavior for an empty module is inconsistent between JVM and KMP

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When applied to K/JVM module, BCV require to create an API dump even if a module does not have any "production" sources (for instance, it's a test-only module).

At the same time, if it's KMP module, BCV simply ignores the module (instead of reporting an error and asking to create an empty dump).

KLib support complicated the matter:

• in 0.15.0-Beta.{1,2} such a module will be ignored, the same way it's done for JVM ABI validation;
• develop branch contains what should become 0.15.0-Beta.3 and KLib validation fails for an empty module (the same way it would fail for a K/JVM empty module).

BCV should validation should behave consistently for both JVM and KLib ABI as well as both K/JVM and KMP projects.
Current JVM ABI validation behavior for KMP projects seems to be incorrect as sources removal will lead to the :apiCheck task being skipped instead of it being executed and failed.