libfuse: fix tests to work with SyncAll
libfuse: fix tests to work with SyncAll

Issue: KBFS-2076

keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/kbfs,keybase/client,keybase/client,keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/kbfs,keybase/client