[e.cash] Add Guarda wallet

Summary: Adding guarda wallet to /wallets

Test Plan: Preview the site and go to /wallets. Find Guarda wallet and check it looks good and the link works

Reviewers: #bitcoin_abc, bytesofman

Reviewed By: #bitcoin_abc, bytesofman

Subscribers: bytesofman

Differential Revision: https://reviews.bitcoinabc.org/D14523