fix minor unreachable code caused by t.Fatal

[Abirdcfly]

Signed-off-by: Abirdcfly fp544037857@gmail.com

see https://go.dev/play/p/EKemzC-_Uk4 for example:

package main

import (
	"testing"
)

func TestLastIndex(t *testing.T) {
	t.Fatalf("print this line")
	t.Log("not print")
}

/* output:
=== RUN   TestLastIndex
    prog.go:8: print this line
--- FAIL: TestLastIndex (0.00s)
FAIL

Program exited.
*/