Don't you have a backup of your system?
If the file was there and you deleted it's not a problem, that location is just a "storage" place. If you want to retrieve groups from a database (while keeping authentication in your LDAP) then you need that file, if not you can stay without.
The process of setting up the BISQLGroupProvider is covered in the doc: Configuring Oracle Business Intelligence to Use Alternative Authentication Providers
If you need it and you don't have a backup I would suggest to setup a backup procedure first and then you can probably take it from another identical version (strictly same version to avoid issues) and copy it over.