If I run 'delete 0' or 'view -1', the error message the user gets is "Invalid command format!...". Instead, it should be the same error message as if the user uses a index out of bound like "The expense index provided is invalid". <!--session: 1604045063796-86271cbd-68aa-4462-80e5-3dc3e014780e-->
If I run 'delete 0' or 'view -1', the error message the user gets is "Invalid command format!...".
Instead, it should be the same error message as if the user uses a index out of bound like "The expense index provided is invalid".