Remove unecessary height in Withdraw Modal

[pimato]

Describe the task that needs to be done
It looks like our min-height for the withdraw modal is set too high. Currently at 510px it leads to this:

You can trigger the issue if you pick an asset which you have not available in the Omen Account.

Describe how you have considered doing it
Either reducing the min-height requirement or remove it completely.

Describe how do you expect to test the task resolution

• Withdraw modal has no unecessary gaps in height.