md_journal: fix off-by-one error in atLeastNNonLocalSquashes (#556)
md_journal: fix off-by-one error in atLeastNNonLocalSquashes (#556)

Issue: KBFS-1747
keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/kbfs,keybase/client,keybase/kbfs,keybase/client