[Chronik] Add support for MINT txs in slp::parse

Summary:
This has previously been unimplemented, and this diff adds support for all SLP MINT txs.

There are two different variants:

• V1, NFT1 CHILD, NFT1 GROUP: Use mint baton (by assigning an output as the new mint baton) and have exactly 1 mint amount output. See here for the spec.
• V2 (Mint Vault): Don't use a mint baton, instead require one of the inputs to have a P2SH script with the mint_vault_scripthash as scripthash, and can have 1 to 19 mint amount outputs. See here for the spec.

Test Plan: cargo test -p bitcoinsuite --test test_slp_parse_mint

Reviewers: Fabien, #bitcoin_abc

Reviewed By: Fabien, #bitcoin_abc

Differential Revision: https://reviews.bitcoinabc.org/D15018