Fix unchecked artifact implementation being persisted

Fix unchecked artifact implementation being persisted

Fixes the problem of an interface operation artifact implementation
being persisted even if it is not selected.
After checking that the interface operation has an artifact
implementation and filling up the artifact information, the values
were being persisted if the option is unchecked afterwards.
There was no way to remove the artifact implementation information
once it was persisted for the first time.

Change-Id: I4fdf4027919fdc04d688805bcf0b37fa6869b2e8
Issue-ID: SDC-3918
Signed-off-by: andre.schmid <andre.schmid@est.tech>