Create a state containing valid Sapling and Orchard blocks

[upbqdn]

In #8533, we needed a state which contains:

1. Blocks containing Sapling note commitments.
2. Blocks for which we could activate NU5, see #8534.
3. Blocks containing Orchard note commitments.

There's currently no way to create such a state in Zebra. Having it is beneficial for tests, as mentioned below https://github.com/ZcashFoundation/zebra/blob/824e5200e22438c322914cd776f0b89808a98e97/zebra-rpc/src/methods/tests/snapshot.rs#L54-L63

Depends on #8534.

[mpguerra]

@ZcashFoundation/zebra-team Is this still relevant?

[upbqdn]

Yes, it is. We currently don't have such a state in the tests.