[server] Fixed issue with the adapters cache of a cloned EditedEntity
The adapters' cache of the entity within an EditedEntity used to be copied along
the entity itself during a cloning operation of the EditedEntity. This raises
an issue when the adapters' cache is not empty and contains cached values
linking to transaction-specific data (or the transaction itself). This prevents
the clone EditedEntity being used in a transaction outside the one that created
it.
This change resets the adapters' cache of the new copy so that no cached value
remain. The new copy can then be used in a new transaction afterwards.