Modify the role used to backup

Not a good practice to use superuser for automatic tasks, so now the script uses the `backup` user.

CommonScripts/j7back

@@ -4,6 +4,6 @@
 
 echo 'Backing up jovian platform ...'
 
-ssh -p 7025 jovian-hersemeule.eu 'pg_dumpall --username=postgres --no-password > /home/jovian/LocalDocs/BackupPostgres/dumpfile'
+ssh -p 7025 jovian-hersemeule.eu 'pg_dumpall --username=backup --no-password > /home/jovian/LocalDocs/BackupPostgres/dumpfile'
 
 echo 'End'