[Cashtab] Upgrade slpv1 send txs

Summary: Use upgraded ecash-coinselect to create slpv1 token send txs.

Test Plan: npm test

Reviewers: #bitcoin_abc, PiRK

Reviewed By: #bitcoin_abc, PiRK

Subscribers: PiRK

Differential Revision: https://reviews.bitcoinabc.org/D15519