Regression on 5.6.11 when using a column referencing a composite user type which is immutable.

Caused by changes to HHH-15359 Closed in particular https://github.com/hibernate/hibernate-orm/commit/fd3ab8b7cfb21f7fd14e628f6f33ed532757836a#diff-3c65a34844742881c48196badd6f79bd00e6d45161a11dbc0868a2e0c134157cR260 fails to work with a custom/composite user type which is immutable (ref. CompositeUserType#isMutable) and therefore doesn't support CompositeUserType#setPropertyValue.

Might be necessary to adapt the check in TypeHelper#replaceAssociations to assure the type is mutable before trying to manipulate it:

				if ( componentType.isMutable() && target[i] != null && objects != null ) {
					// Need to account for entity mode on the CompositeType interface, that seems not been used by any implementation
					componentType.setPropertyValues( target[i], objects, EntityMode.POJO );
				}