Remove FakeBackendV2 import deprecated in Qiskit 0.46 (backport #1420) (

#1422)

This is an automatic backport of pull request #1420 done by
[Mergify](https://mergify.com).


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Co-authored-by: Elena Peña Tapia <[email protected]>

qiskit_experiments/framework/backend_data.py

@@ -18,9 +18,24 @@ class unifies data access for various data fields.
 from qiskit.providers.models import PulseBackendConfiguration
 from qiskit.providers import BackendV1, BackendV2
 from qiskit.providers.fake_provider import FakeBackend
-from qiskit.providers.fake_provider.fake_backend import FakeBackendV2
 from qiskit.utils.deprecation import deprecate_func
 
+try:
+    # Removed in Qiskit 1.0.
+    from qiskit.providers.fake_provider.fake_backend import FakeBackendV2
+except ImportError:
+
+    class FakeBackendV2:
+        """Dummy class for when FakeBackendV2 import fails
+
+        This class is only used in isinstance checks. If the import fails, then
+        there won't be an instance of the class either so any dummy class is
+        fine.
+        """
+
+        pass
+
+
 try:
     # Removed in Qiskit 1.0. Different from the other FakeBackendV2's
     from qiskit.providers.fake_provider import QiskitFakeBackendV2