[tg bot] change link name for token document url

Summary:
T2972

Depends on D13283

Change link name for token document url in genesis txs from 'url' to '[doc]'

Test Plan:
npm test
npm run msgs and observe new link title

Reviewers: #bitcoin_abc, emack

Reviewed By: #bitcoin_abc, emack

Differential Revision: https://reviews.bitcoinabc.org/D13284