Join every individual map iteration with " "
Join every individual map iteration with " "

- Rationale: Array.map() function actually calls join() on each element
it iterates through, and this causes the template string to have
arbitrary commas. We can join with a blank string instead to undo this
behavior resulting from toString().

googleinterns/step27-2020,googleinterns/step27-2020,googleinterns/step27-2020