CodePipeline - Path filtering for github source

[QuiveringZen]

Hello,

In my github repository I have several folders, however I only want the CodePipeline to trigger, when I make a change in a certain folder. I believe this is achieved using FilterGroup.andFilePathIs(pathRegex). However if I make a change in another folder and push, the build is still triggered for me, maybe we could have some improvement on how to property craft the path regex?