Remove bound on qiskit-aer version (#1306)

Author: wshanks

requirements-extras.txt

@@ -1,5 +1,5 @@
 qiskit-ibm-provider>=0.6.1 # for submitting experiments to backends through the IBM provider
 cvxpy>=1.3.2 # for tomography
 scikit-learn # for discriminators
-qiskit-aer>=0.11.0,<=0.12.2 # Temporary version pin because of https://github.com/Qiskit-Extensions/qiskit-experiments/issues/1292
+qiskit-aer>=0.11.0
 qiskit_dynamics>=0.4.0 # for the PulseBackend