path: change `posix.join` to use array
Change posix.join
to use array.join
instead of additional assignment.
confidence improvement accuracy (*) (**) (***)
path/join-posix.js n=100000 paths='/foo|bar||baz/asdf|quux|..' *** 5.95 % ±1.42% ±1.90% ±2.49%