[Cashtab] Do not render mint switch on token page unless user has mint baton

Summary:
Token action page should conditionally render only available options. The Mint option with a long explanation of why it is disabled is not helpful.

Just do not render the mint option if it is not available.

Test Plan: npm test

Reviewers: #bitcoin_abc, emack

Reviewed By: #bitcoin_abc, emack

Differential Revision: https://reviews.bitcoinabc.org/D15998