Documentation [arrays] doesn't match example code

[rbellabre]

Love the series, thanks for taking the time to make it.

In this refactor: https://github.com/quii/learn-go-with-tests/blob/main/arrays/v7/sum_test.go

...
	checkSums := func(t testing.TB, got, want []int) {
...

The expected parameter is the interface type, whereas all versions in the code repo use a pointer to type T:

• https://github.com/quii/learn-go-with-tests/blob/main/arrays/v7/sum_test.go
• https://github.com/quii/learn-go-with-tests/blob/main/arrays/v8/sum_test.go

... 
	checkSums := func(t *testing.T, got, want []int) {
...

Since interfaces aren't covered until the next chapter and the example code differs from the documentation, it wasn't clear if this was intentional or not.