cleanup gossip_digest.idl
cleanup gossip_digest.idl

Remove uuid class, nonexistent application states and add ';'.

raphaelsc/scylla,avikivity/scylla,raphaelsc/scylla,avikivity/scylla,kjniemi/scylla,kjniemi/scylla,scylladb/scylla,raphaelsc/scylla,duarten/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla,duarten/scylla,duarten/scylla,kjniemi/scylla