This function creates a local variable called factors and initializes it to an empty array.
It then loops through every integer value from 1 up to n (the number that was given as an
argument) and adds it to the array of factors using the push() method if it's a factor. We
test if it's a factor by seeing if the answer leaves a whole number with no remainder when
n is divided by the integer i (the definition of a factor).
Try running the test again by refreshing the SpecRunner.html page. It should look similar