fix comment

Author: JonathanOppenheimer

utils/rand/rand.go

@@ -14,7 +14,7 @@ import (
 // Intn is a shortcut for generating a random integer between 0 and
 // n using crypto/rand.
 func Intn(n int64) int64 {
-	// We can guarantee that rand.Int(rand.Reader will never error), and thus
+	// We can guarantee that rand.Int(rand.Reader...) will never error, and thus
 	// we can safely ignore the error.
 	//
 	// See https://go.dev/src/crypto/rand/rand.go