Merge bitcoin/bitcoin#31751: test: fix intermittent timeout in p2p_1p1c_network.py

152a2dc test: fix intermittent timeout in p2p_1p1c_network.py (Martin Zumsande)

Pull request description:

  The timeout is due to outstanding txrequests with python peers, which have the same timeout (`60s`) as the mempool sync timeout.
  I explained this in more detail in bitcoin/bitcoin#31721 (comment) and also mentioned there how to reproduce it.

  Fix this by disconnecting the python peers after they send their txns, they aren't needed after this point anyway because the main goal of the test is the sync between the 4 full nodes.

  Fixes #31721

ACKs for top commit:
  achow101:
    ACK 152a2dc
  instagibbs:
    reACK 152a2dc
  marcofleon:
    ACK 152a2dc
  glozow:
    reACK 152a2dc

Tree-SHA512: 908c58933d8e9fcca91425fce1b7c9c7cb7121a6d26840630e03a442356ad2a327d1e087df72a19caa97024ea827593e10f2ff93838f88939458e73df9857df0

Author: achow101

test/functional/p2p_1p1c_network.py

@@ -144,6 +144,11 @@ def run_test(self):
             for tx in transactions_to_presend[i]:
                 peer.send_and_ping(msg_tx(tx))
 
+        # Disconnect python peers to clear outstanding orphan requests with them, avoiding timeouts.
+        # We are only interested in the syncing behavior between real nodes.
+        for i in range(self.num_nodes):
+            self.nodes[i].disconnect_p2ps()
+
         self.log.info("Submit full packages to node0")
         for package_hex in packages_to_submit:
             submitpackage_result = self.nodes[0].submitpackage(package_hex)