[FIX] RT-2412 Knox tab: Fix styling, strings

- Add header, left line to make it standard with other tab styles

- Fix problem with the underline "bleeding" into the space left to it

- Replace string "Something went wrong, please contact SnapSwap support." with "We are unable to proceed with instant deposit. Please contact support@snapswap.us."

- Replace string "Verify your identity to deposit USD. Verify identity." with "Verify your identity to deposit USD (US-only)."

- Fix verify link space underlining.

- Fix typos.