selftests/bpf: Test bpf_skb_change_tail() in TC ingress

Similarly to the previous test, we also need a test case to cover
positive offsets as well, TC is an excellent hook for this.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Zijian Zhang <zijianzhang@bytedance.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20241213034057.246437-5-xiyou.wangcong@gmail.com