message: test: add p2p_lock acquires in p2p_leak_tx.py
diff: """Test that we don't leak txs to inbound peers that we haven't yet announced to"""
  from test_framework.messages import msg_getdata, CInv, MSG_TX
  -from test_framework.p2p import P2PDataStore
  +from test_framework.p2p import p2p_lock, P2PDataStore
  from test_framework.test_framework import BitcoinTestFramework
  from test_framework.util import (
  assert_equal,
  @@ -39,6 +39,7 @@ class P2PLeakTxTest(BitcoinTestFramework):
  want_tx = msg_getdata()
  want_tx.inv.append(CInv(t=MSG_TX, h=int(txid, 16)))
  + with p2p_lock:
  inbound_peer.last_message.pop('notfound', None)
  inbound_peer.send_and_ping(want_tx)
  @@ -46,6 +47,7 @@ class P2PLeakTxTest(BitcoinTestFramework):
  self.log.debug('tx {} was not yet announced to us.'.format(txid))
  self.log.debug("node has responded with a notfound message. End test.")
  assert_equal(inbound_peer.last_message['notfound'].vec[0].hash, int(txid, 16))
  + with p2p_lock:
  inbound_peer.last_message.pop('notfound')
  break
  else:
  