The links on forums should exclude chars like ')' that immediately follow them
Here's an example: https://forum.nim-lang.org/t/6146#38114

![image](https://user-images.githubusercontent.com/3578197/78794637-041de980-7982-11ea-8ec7-ebe783de7e05.png)

Above, clicking that link leads to an invalid link: `https://github.com/nim-lang/Nim/pull/13919)` (GitHub will auto-remove that trailing `)` because it does the parsing correctly).

While this a fixed, it would be nice to add a test where, an another command char after links.. `.` is also excluded from the links.