docstr: Test that state measurements with no observable work as expected.
docstr_tok: ["Test","that","state","measurements","with","no","observable","work","as","expected","."]
code: def test_state_measurement_no_obs(self, measurement, expected):
      """Test that state measurements with no observable work as expected."""
      state = -0.5j * np.ones((2, 2))
      res = measure(measurement, state)
  
      assert np.allclose(res, expected)
  
imports: import pytest
  import numpy
  from scipy.sparse import csr_matrix
  import pennylane
  from pennylane.devices.qubit import simulate
  from pennylane.devices.qubit.measure import measure, state_diagonalizing_gates, csr_dot_products, full_dot_products, get_measurement_function, sum_of_terms_method
label_desc: Use image node_id 1 for calling the TestMeasurements obj's underlying member method code with example usage: obj.test_state_measurement_no_obs(measurement, expected) without return types