qa: Use node.datadir instead of tmpdir in test framework

test/functional/rpc_bind.py

@@ -48,7 +48,7 @@ class RPCBindTest(BitcoinTestFramework):
         self.nodes[0].rpchost = None
         self.start_nodes([base_args])
         # connect to node through non-loopback interface
-        node = get_rpc_proxy(rpc_url(get_datadir_path(self.options.tmpdir, 0), 0, "%s:%d" % (rpchost, rpcport)), 0, coveragedir=self.options.coveragedir)
+        node = get_rpc_proxy(rpc_url(self.nodes[0].datadir, 0, "%s:%d" % (rpchost, rpcport)), 0, coveragedir=self.options.coveragedir)
         node.getnetworkinfo()
         self.stop_nodes()