[Cashtab] Create custom modal for version upgrades

Summary:
The antd notification is not properly triggering updates. Also, we want to move alway from antd entirely. Will happen incrementally.

Here is one step.

Test Plan:
npm test

How I tested it

• deploy to netlify prod site
• bump the version and deploy it again
• bump the version and deploy it again

clicking ok refreshed the page and updated the version, as expected
clicking 'later' hid the modal and did nothing, as expected

Reviewers: #bitcoin_abc, PiRK, emack

Reviewed By: #bitcoin_abc, PiRK, emack

Subscribers: emack

Differential Revision: https://reviews.bitcoinabc.org/D15684