concurrent submissions do not smartly iterate on id numbers

When there are two concurrent submissions, they will both be referenced to main, so will have the same id number. That means merges will have to be done one at a time, and after the first, the action for the subsequent submission should be rerun. Perhaps open issues with new-contribution should all rerun upon changes to main?

首先跟踪处理带有 new-contribution 标签的开放 issue 的 action，以及提交如何引用 main 并获得 ID 编号。当并发提交能够在不发生 ID 冲突的情况下得到处理，并且预期的重新运行行为已定义并验证后，这项工作就完成了。