message: test: Use Popen.wait instead of RPC in assert_start_raises_init_error
diff: @@ -485,11 +485,8 @@ class TestNode():
  tempfile.NamedTemporaryFile(dir=self.stdout_dir, delete=False) as log_stdout:
  try:
  self.start(extra_args, stdout=log_stdout, stderr=log_stderr, *args, **kwargs)
  - self.wait_for_rpc_connection()
  - self.stop_node()
  - self.wait_until_stopped()
  - except FailedToStartError as e:
  - self.log.debug('bitcoind failed to start: %s', e)
  + ret = self.process.wait(timeout=self.rpc_timeout)
  + self.log.debug(self._node_msg(f'bitcoind exited with status {ret} during initialization'))
  self.running = False
  self.process = None
  # Check stderr for expected message
  @@ -508,11 +505,15 @@ class TestNode():
  if expected_msg != stderr:
  self._raise_assertion_error(
  'Expected message "{}" does not fully match stderr:\n"{}"'.format(expected_msg, stderr))
  - else:
  + except subprocess.TimeoutExpired:
  + self.process.kill()
  + self.running = False
  + self.process = None
  + assert_msg = f'bitcoind should have exited within {self.rpc_timeout}s '
  if expected_msg is None:
  - assert_msg = "bitcoind should have exited with an error"
  + assert_msg += "with an error"
  else:
  - assert_msg = "bitcoind should have exited with expected error " + expected_msg
  + assert_msg += "with expected error " + expected_msg
  self._raise_assertion_error(assert_msg)
  def add_p2p_connection(self, p2p_conn, *, wait_for_verack=True, **kwargs):
  