CONTRIBUTION.md can't display the format of commit message normally

[Faldict]

I think the tabs between <code> and </code> have been transferred. So may be you should add \.

[gaocegege]

Yeah, It is a bug.

Actually I tried to use ``` but it seems that golang misunderstands it with raw strings.

Thanks, I'll fix it.

[Faldict]

高策哥哥怎么有这么多时间开新坑 @gaocegege

[gaocegege]

@Faldict Actually, this repo costs me only 5 hours.

鲁迅说过，时间就像XX，挤一下就有了

[gaocegege]

而且还有一点，很多坑都不维护了，所以时间就多了。。

[gaocegege]

Partially done, if you are not satisfied, feel free to reopen the issue.