test: fix intermittent failure in p2p_leak_tx.py

Author: mzumsande

test/functional/p2p_leak_tx.py

@@ -57,6 +57,7 @@ def test_notfound_on_replaced_tx(self):
         tx_b = tx_a["tx"]
         tx_b.vout[0].nValue -= 9000
         self.gen_node.sendrawtransaction(tx_b.serialize().hex())
+        inbound_peer.wait_until(lambda: "tx" in inbound_peer.last_message and inbound_peer.last_message.get("tx").tx.getwtxid() == tx_b.getwtxid())
 
         self.log.info("Re-request of tx_a after replacement is answered with notfound")
         req_vec = [