remove deprecated clifford get/set item (#11555)

* remove deprecated clifford getitem and setitum

* add release note

* Update releasenotes/notes/deprecate_clifford_indexing-5e3500301a696bdc.yaml

Co-authored-by: Julien Gacon <gaconju@gmail.com>

* Update releasenotes/notes/deprecate_clifford_indexing-5e3500301a696bdc.yaml

---------

Co-authored-by: Luciano Bello <bel@zurich.ibm.com>
Co-authored-by: Julien Gacon <gaconju@gmail.com>

qiskit/quantum_info/operators/symplectic/clifford.py

@@ -30,7 +30,6 @@
 from qiskit.quantum_info.operators.operator import Operator
 from qiskit.quantum_info.operators.scalar_op import ScalarOp
 from qiskit.quantum_info.operators.symplectic.base_pauli import _count_y
-from qiskit.utils.deprecation import deprecate_func
 from qiskit.synthesis.linear import calc_inverse_matrix
 
 from .base_pauli import BasePauli
@@ -228,24 +227,6 @@ def copy(self):
 
     # pylint: disable=bad-docstring-quotes
 
-    @deprecate_func(
-        since="0.24.0",
-        package_name="qiskit-terra",
-        additional_msg="Instead, index or iterate through the Clifford.tableau attribute.",
-    )
-    def __getitem__(self, key):
-        """Return a stabilizer Pauli row"""
-        return self.table.__getitem__(key)
-
-    @deprecate_func(
-        since="0.24.0",
-        package_name="qiskit-terra",
-        additional_msg="Use Clifford.tableau property instead.",
-    )
-    def __setitem__(self, key, value):
-        """Set a stabilizer Pauli row"""
-        self.tableau.__setitem__(key, self._stack_table_phase(value.array, value.phase))
-
     @property
     def symplectic_matrix(self):
         """Return boolean symplectic matrix."""

releasenotes/notes/deprecate_clifford_indexing-5e3500301a696bdc.yaml

@@ -0,0 +1,6 @@
+---
+upgrade:
+  - |
+    Remove deprecated ``__getitem__``/``__setitem__`` magic methods of 
+    :class:`~qiskit.quantum_info.operators.symplectic.Clifford`.
+    The methods were deprecated since Qiskit 0.44, released on July 2023. Instead, index or iterate through the :attr:`.Clifford.tableau` attribute.