fix(test): fix test_4_20_kill1

Fixes #3141

Test plan
---------
test_4_20_kill1

test-utils/testlib/src/node/process_node.rs

@@ -15,6 +15,10 @@ use neard::config::NearConfig;
 use crate::node::Node;
 use crate::user::rpc_user::RpcUser;
 use crate::user::User;
+use actix::{Actor, System};
+use futures::{FutureExt, TryFutureExt};
+use near_jsonrpc_client::new_client;
+use near_network::test_utils::WaitOrTimeout;
 
 pub enum ProcessNodeState {
     Stopped,
@@ -46,7 +50,24 @@ impl Node for ProcessNode {
                 let child =
                     self.get_start_node_command().spawn().expect("start node command failed");
                 self.state = ProcessNodeState::Running(child);
-                thread::sleep(Duration::from_secs(3));
+                let addr = self.config.rpc_config.addr.clone();
+
+                System::run(|| {
+                    WaitOrTimeout::new(
+                        Box::new(move |_| {
+                            actix::spawn(
+                                new_client(&format!("http://{}", addr))
+                                    .status()
+                                    .map_ok(|_| System::current().stop())
+                                    .map(drop),
+                            )
+                        }),
+                        500,
+                        5000,
+                    )
+                    .start();
+                })
+                .unwrap();
             }
             ProcessNodeState::Running(_) => panic!("Node is already running"),
         }