Translate error message to bulgarian on create new money transfer

[Tuscann]

Which area(s) of Podkrepi.bg are affected?

Admin panel

Describe the Bug

Need translation of error message to to bulgarian.

To Reproduce

1. Login with random user. (Maybe admin user in future)
2. Open https://podkrepi.bg/admin/withdrawals/create
3. Click button "Изпрати".
4. Check error message of field "Въведена Сума".
5. Now show error message "amount must be a positive number"

Expected Behavior

Message to be "Сумата трябва да е положителна.".

Which browser are you using? (if relevant)

Floorp Brave Firefox