We can add Github Action for automatically check licenses and review future pull requests.

This topic was first mentioned in #303 (comment) and i had realy work for it.

Some result you can see https://github.com/liangyuanpeng/incubator-eventmesh/pull/1 .

How can we use github-actions bot robot instead of myself? Thanks @kezhenxu94