[alias-server] Add USD price info to telegram bot msgs

Summary:
T2970

Depends on D13247

Telegram bot gives USD price of registration, if available.

Test Plan: node index.js, register some aliases. Check that correct XEC price appears in logs. Tg bot messages will probably say $0 USD for now since prices are set so low for testing.

Reviewers: #bitcoin_abc, emack

Reviewed By: #bitcoin_abc, emack

Differential Revision: https://reviews.bitcoinabc.org/D13248