table: disable_auto_compaction: stop ongoing compactions
table: disable_auto_compaction: stop ongoing compactions

The api call disables new regular compaction jobs from starting
but it doesn't wait for ongoing compaction to stop and so it's
much less useful.

Returning after stopping regular compaction jobs and waiting
for them to stop guarantees that no regular compactions job are
running when nodetool disableautocompaction returns successfully.

Fixes #9313

Test: sstable_compaction_test,sstable_directory_test(dev)

Signed-off-by: Benny Halevy <23c997c90eb8537635e9392d48e7af1bf1b2ca22@scylladb.com>

scylladb/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla