db/view: Consider partition tombstone when generating updates
db/view: Consider partition tombstone when generating updates

Not adding the partition tombstone to the current list of tombstones
may cause updates to be incorrectly generated.

Signed-off-by: Duarte Nunes <a60e8b7496f7715d71354fe4c06dd24017025bf1@scylladb.com>

scylladb/scylla,duarten/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla,duarten/scylla,scylladb/scylla,duarten/scylla,avikivity/scylla,avikivity/scylla