Use error mitigation when doing VQE

[FarLab]

Add an option to use error mitigation when running a VQE. We could start with zero noise extrapolation using mitiq.

[FarLab]

Maybe a more suitable/straightforward error mitigation technique is read out error mitigation, for example: https://journals.aps.org/prxquantum/abstract/10.1103/PRXQuantum.2.040326

[nathanshammah]

A way to start could be to have a tutorial applying QEM with Mitiq. There are several examples to start from, including with VQE, https://mitiq.readthedocs.io/en/stable/examples/examples.html.