Hi Folks,
Have you tried "request system storage cleanup" in the box?
Since deleting the below files manually is not a good idea,
-rw-r----- 1 root config 24117248 Jan 2 13:16 juniper.data
-rw-r----- 1 root config 23592960 Jan 2 13:23 juniper.data+
-rw-r----- 1 root config 1048576 Jan 2 13:26 juniper.db