Give wait_for_pings more time

Large reorgs as in the p2p-fullblocktest can cause very long long delays
for the ping that we're waiting for. This was not a problem before dashpay#2593,
as before this wait_until was waiting forever.

qa/rpc-tests/test_framework/comptool.py

@@ -197,10 +197,10 @@ def veracked():
             return all(node.verack_received for node in self.test_nodes)
         return wait_until(veracked, timeout=10)
 
-    def wait_for_pings(self, counter):
+    def wait_for_pings(self, counter, timeout=float('inf')):
         def received_pongs():
             return all(node.received_ping_response(counter) for node in self.test_nodes)
-        return wait_until(received_pongs)
+        return wait_until(received_pongs, timeout=timeout)
 
     # sync_blocks: Wait for all connections to request the blockhash given
     # then send get_headers to find out the tip of each node, and synchronize
@@ -222,7 +222,7 @@ def blocks_requested():
 
         # Send ping and wait for response -- synchronization hack
         [ c.cb.send_ping(self.ping_counter) for c in self.connections ]
-        self.wait_for_pings(self.ping_counter)
+        self.wait_for_pings(self.ping_counter, timeout=300)
         self.ping_counter += 1
 
     # Analogous to sync_block (see above)
@@ -358,7 +358,7 @@ def run(self):
                         else:
                             [ c.send_message(msg_block(block)) for c in self.connections ]
                             [ c.cb.send_ping(self.ping_counter) for c in self.connections ]
-                            self.wait_for_pings(self.ping_counter)
+                            self.wait_for_pings(self.ping_counter, timeout=300)
                             self.ping_counter += 1
                         if (not self.check_results(tip, outcome)):
                             raise AssertionError("Test failed at test %d" % test_number)