UI displays the wrong amount for spending limits

[usame-algan]

Bug description

• When creating a spending limit transaction, the UI displays the full amount instead of amount - spent.
• The spacing inside the modal also looks a bit off

Steps to reproduce

1. Open a Safe
2. Create a new spending limit for your wallet
3. Execute a spending limit transaction
4. Observe that it displays the correct spent amount on the settings page
5. Create a new spending limit transaction
6. Observe that it still displays the original amount

Expected result

• It should display the full amount - spent amount inside the modal
• The area should have consistent top and bottom spacing

Obtained result

It displays the full amount inside the modal

Screenshots

In this case a transaction with 100 SAFE was already executed but it still displays 500 instead of 400. Going to the next step results in an error that is not caught in the UI.