Add scrollbar to payment account popups [0.25 XMR]
This issue requests adding a scrollbar to popups for payment account terms if they're too long to fit on the screen, which can happen with low resolution screens.

For example, the popup with terms for the "Pay by Mail" payment account is long:

<img width="821" alt="image" src="https://github.com/haveno-dex/haveno/assets/13068859/f4d1da0b-db93-4224-9520-10ebdddef0f9">
