message: Remove redundant p2p lock tacking for tx download functional tests
  New functional test coverage of tx download was added by
  but `with p2p_lock` is redundant for some tests with `wait_until`
  test helper, already guaranteeing test lock tacking.
diff: @@ -169,8 +169,6 @@ class TxDownloadTest(BitcoinTestFramework):
  assert_equal(peer_fallback.tx_getdata_count, 0)
  self.nodes[0].setmocktime(int(time.time()) + GETDATA_TX_INTERVAL + 1) # Wait for request to peer_expiry to expire
  peer_fallback.wait_until(lambda: peer_fallback.tx_getdata_count >= 1, timeout=1)
  - with p2p_lock:
  - assert_equal(peer_fallback.tx_getdata_count, 1)
  self.restart_node(0) # reset mocktime
  def test_disconnect_fallback(self):
  @@ -188,8 +186,6 @@ class TxDownloadTest(BitcoinTestFramework):
  peer_disconnect.peer_disconnect()
  peer_disconnect.wait_for_disconnect()
  peer_fallback.wait_until(lambda: peer_fallback.tx_getdata_count >= 1, timeout=1)
  - with p2p_lock:
  - assert_equal(peer_fallback.tx_getdata_count, 1)
  def test_notfound_fallback(self):
  self.log.info('Check that notfounds will select another peer for download immediately')
  @@ -205,8 +201,6 @@ class TxDownloadTest(BitcoinTestFramework):
  assert_equal(peer_fallback.tx_getdata_count, 0)
  peer_notfound.send_and_ping(msg_notfound(vec=[CInv(MSG_WTX, WTXID)])) # Send notfound, so that fallback peer is selected
  peer_fallback.wait_until(lambda: peer_fallback.tx_getdata_count >= 1, timeout=1)
  - with p2p_lock:
  - assert_equal(peer_fallback.tx_getdata_count, 1)
  def test_preferred_inv(self, preferred=False):
  if preferred:
  @@ -243,8 +237,6 @@ class TxDownloadTest(BitcoinTestFramework):
  assert_equal(peer.tx_getdata_count, 0 if glob_wtxid else 1)
  self.nodes[0].setmocktime(mock_time + TXID_RELAY_DELAY)
  peer.wait_until(lambda: peer.tx_getdata_count >= 1, timeout=1)
  - with p2p_lock:
  - assert_equal(peer.tx_getdata_count, 1)
  def test_large_inv_batch(self):
  self.log.info('Test how large inv batches are handled with relay permission')
  @@ -259,8 +251,6 @@ class TxDownloadTest(BitcoinTestFramework):
  peer.send_message(msg_inv([CInv(t=MSG_WTX, h=wtxid) for wtxid in range(MAX_PEER_TX_ANNOUNCEMENTS + 1)]))
  peer.wait_until(lambda: peer.tx_getdata_count == MAX_PEER_TX_ANNOUNCEMENTS)
  peer.sync_with_ping()
  - with p2p_lock:
  - assert_equal(peer.tx_getdata_count, MAX_PEER_TX_ANNOUNCEMENTS)
  def test_spurious_notfound(self):
  self.log.info('Check that spurious notfound is ignored')
  