core: fix transferClientType deserialization

The existence of the unusef toString method breaks jackson
deseralization for the transferClientType parameter. Since this
parameter should always be set and toString is not used, this patch
simply removes this method.

Bug-Url: https://bugzilla.redhat.com/2123008
Signed-off-by: Benny Zlotnik <bzlotnik@redhat.com>

backend/manager/modules/common/src/main/java/org/ovirt/engine/core/common/businessentities/storage/TransferClientType.java

@@ -31,11 +31,6 @@ public static TransferClientType forValue(int value) {
         return valueToType.get(value);
     }
 
-    @Override
-    public String toString() {
-        return description;
-    }
-
     public boolean isBrowserTransfer() {
         return this == TRANSFER_VIA_BROWSER;
     }