'host' parameter for deleting image has removed from client.
Zun UI should remove this parameter.
Now, due to only 'id' is necessary for deleting image,
we can use 'delete-selected' type action and common deletion
confirmation dialog. Using the common deletion action,
we can also implement deletion action as batch action.
Change-Id: I2adae5cb466e620177c3788ac340f6464711e21d
Closes-Bug: #1799125