[macos] Unmount the directory which is mounted by sshfs in Mac

Just as reference let me quote the osxfuse FAQ

4.8. How should I unmount my "FUSE for OS X" file system? I cannot find the fusermount program anywhere.

Just use the standard umount command in OS X. You do not need the Linux-specific fusermount with "FUSE for OS X".

As mentioned above, either diskutil unmount or umount should work