Update fake backend and fake provider to use versioned interface

[mtreinish]

Summary

As was reported in #6280 the algorithms path doesn't work on minimal
examples of the Backend and Jobs interface and instead only works in
practice on ibmq, aer, or basic aer backends. Part of the reason for
this was that all the testing of algorithms is done exclusively on those
providers and there wasn't a minimal example to test against that
doesn't have legacy overhead (like qobj, etc). This commit updates the
fake providers and fake backends to use the latest version of the
provider, backend, and job interfaces and to be strictly compatible (ie
no qobj support). Besides exercising the new interface version it also
enables us to test the eventual fix for #6280 when it's available.

Details and comments

[jyu00]

The code looks good. However, FakeBackend is widely used (even in Qiskit textbook and tutorials), so dropping Qobj support without warning is a bit risky. It certainly shouldn't be in a patch release even though it's "fake".

[mtreinish]

The code looks good. However, FakeBackend is widely used (even in Qiskit textbook and tutorials), so dropping Qobj support without warning is a bit risky. It certainly shouldn't be in a patch release even though it's "fake".

I wasn't proposing this to be backported or included in a patch release, I agree this isn't valid for that. The tension here is that there actually isn't any backend available for local testing that rejects qobj currently, which only makes issues like #6280 more likely. This felt like the right place to do it since these are the test backends.

It's also worth noting that we do run the tutorials here and none of them failed with this. The textbook might be a different, but I believe they're still using execute which will be seamless. It honestly would be quite odd if the textbook or tutorials were manually constructing a qobjs.

[jyu00]

When I searched for qiskit textbook fake, this was the second result: https://qiskit.org/textbook/ch-appendix/qiskit.html which does use qobj. But if you don't plan on making this a patch release then there should be plenty of time for the textbook to be updated.