[DocDB] Help users map snapshot schedules to dbs more clearly when using yb-admin restore_snapshot_schedule

Jira Link: DB-5622

Description

To perform pitr, a user must pass a snapshot schedule's uuid to the yb-admin restore_snapshot_schedule command. The command doesn't provide any output indicating which database was restored.

To make things easier for users we should modify the command so the link between snapshot schedule and db is clear. The command could possibly be modified to support a db name, or it could print out the name of the db restored when it returns successfully.