fix code style

cirq-core/cirq/ops/common_gates.py

@@ -326,6 +326,7 @@ def _json_dict_(self) -> Dict[str, Any]:
     def _value_equality_values_(self):
         return self._canonical_exponent, self._global_shift, self._dimension
 
+
 class Rx(XPowGate):
     r"""A gate with matrix $e^{-i X t/2}$ that rotates around the X axis of the Bloch sphere by $t$.
 

cirq-core/cirq/ops/common_gates_test.py

@@ -1302,6 +1302,7 @@ def test_wrong_dims():
     with pytest.raises(ValueError, match='Wrong shape'):
         _ = cirq.Z.on(cirq.LineQid(0, dimension=3))
 
+
 def test_json():
     dimension = 3
     x3 = cirq.XPowGate(dimension=dimension)