Stop depending on Circuit Metadata | Upgrade Qiskit-Terra Dependency Cap the Qiskit-Terra version

[grace-harper]

What is the expected behavior?

Running tests yields:

Test the error rates using some repetition codes. ... python3.9/site-packages/qiskit_aer/backends/aerbackend.py:463: DeprecationWarning: Setting metadata to None was deprecated in Terra 0.24.0 and this ability will be removed in a future release. Instead, set metadata to an empty dictionary.
  circ.metadata = metadata

In order to upgrade to Terra 0.24.0, we need to be sure that the metadata isn't necessary for our code to run properly. If it is, we need to create a workaround.

[quantumjim]

Is there any more info on this issue? I don't see this test failure (even when I remove the cap), and I don't know what dependance on metadata is causing it.

[grace-harper]

Same as #365 issue. Handled in PR: #385