rpc: Add hash_type MUHASH to gettxoutsetinfo and add a test

Summary:
This concludes backport of core#19145 [3/3]

https://github.com/bitcoin/bitcoin/pull/19145/commits/0d3b2f643d7da3202c0a0e757539208c4aa7c450
https://github.com/bitcoin/bitcoin/pull/19145/commits/6ccc8fc067bf516cda7bc5d7d721945be5ac2003
https://github.com/bitcoin/bitcoin/pull/19145/commits/e987ae5a554c9952812746c29f2766bacea4b727

Depends on D11162

Test Plan: ninja all check-all

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Subscribers: Fabien

Differential Revision: https://reviews.bitcoinabc.org/D11157