Fix IracWriteSkewTest test

The condition that waits for IRAC to complete is incorrect. During the test, we have a remove operation from LON to be replicated to NYC. In NYC, we have a write.

If the transaction in NYC commits before receiving the removal from LON, it creates a conflict in IRAC (which is correct). The conflict resolution fixes by using the remove from LON. In the end, the key is removed from both sites.

The asserts expect the IRAC replication to be completed before the transaction commit and the sites to have the NYC write.