The default backup naming convention adds a timestamp to Snapshot copy names that helps you identify when the copies were created. Unfortunately, this is not something you can remove but you can use the rename options to change the snapshot name after creation from Ontap.
Snapshot copy names can be customized by selecting "Use custom name format for Snapshot copy". By default, the time stamp suffix is added to the Snapshot copy name which helps you identify when the copies were created. Time stamp cannot be removed.