Which friend told Job that "man is born to trouble as surely as sparks fly upward"?

Answer: Eliphaz

The line comes from Eliphaz the Temanite's first speech (Job 4–5), the first reply to Job's lament.

“Then Eliphaz the Temanite replied: Yet man is born to trouble as surely as sparks fly upward.”— Job 4:1, 5:7 (BSB)