Error message: Ledger name already in use

Purpose: When creating a ledger record the system will not allow the user to use a ledger name that is already in use. The user should be made aware of this when creating the ledger.

User story statement(s):

As a Finance managing librarian
I want to be made aware that i can NOT create a ledger with a duplicate Name
so that I know why my ledger will not save successfully

Scenarios:

1. Scenario:
   • Given user is creating ledger
   • When inputting a name that is already being used by another ledger
   • Then the ui displays validation message "This Ledger name is already in use"