Fixes `KeyError` when transpling to a QPU in Krylov tutorial

[henryzou50]

Resolves the issue of KeyError: (0, 14) when doing twoq_gate_err = target[op_name][q].error as we transpile to a QPU. The fix here is to add the if_else instruction to the backend, as the op_namecan be if_else. With this fix, the notebook will run successfully with the latest versions of the requirements.

[qiskit-bot]

One or more of the following people are relevant to this code:

• @annaliese-estes
• @miamico

[review-notebook-app[bot]]

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[miamico]

BTW there are some further comment on this tutorial as part of this issue #4265