Check real hardware path on IBMQ tutorial

[cosenal]

Set variable USE_REAL_HARDWARE to True in https://mitiq.readthedocs.io/en/stable/examples/ibmq-backends.html and check whether the notebook runs correctly. Notice that backend.run has been sunsetted, so this may require updating the way we use the Qiskit API.

[bdg221]

The following error is seen due to the backend.run deprecation:

IBMBackendApiError: 'Error submitting job: \'404 Client Error: Not Found for url: https://api.quantum.ibm.com/runtime/jobs. {"errors":[{"code":1211,"message":"Program not found.","solution":"Make sure you use a valid program name, such as \\\'sampler\\\' or \\\'estimator\\\'. Qiskit Runtime no longer supports the \\\'backend.run\\\' interface. Refer to the migration guide (https://docs.quantum.ibm.com/migration-guides/qiskit-runtime) for instructions to migrate to the primitives.","more_info":"https://docs.quantum-computing.ibm.com/errors"}]}\''

The following files have this issue:

NOTE!!!!
pennylane-ibmq-backends.md includes a TODO for when Pennylane supports Qiskit 1.0. When cleaning up code for using IBM hardware, it would make sense to also complete this TODO.