Change number_of_decimal_places into numpy style error

[junnaka51]

TODO

• [x] circuit.assert_ancilla_is_zero and assert_is_zero 👉 https://github.com/QuantestPy/quantestpy/issues/109
• [x] state_vector.py, operator.py, circuit.assert_equal_to_operator() and circuit.assert_equal() 👉 https://github.com/QuantestPy/quantestpy/issues/111
• [x] state_vector.assert_is_normalized 👉 https://github.com/QuantestPy/quantestpy/issues/116
• [x] operator.assert_is_unitary 👉 https://github.com/QuantestPy/quantestpy/issues/117

[junnaka51]

done