Should I commit shinytest expected json/png files to the master repo?

I've just begun using shinytest on an app that has existed on a github repository for some time.

The shinytest package generates expected .png and .json files for each test.

I can see the need to store this info on so that people can track changes but to me, it seems a bit perverse and impractical keeping these files as png/json files on the repo for the following reasons.

1. when these files change it creates a huge and illegible git diff that reviewers will struggle to sift through.
2. the repo will balloon in size.
3. I've always been told it's best practise to store large files like data on git. So storing json and png which as text are thousands of lines long.

I'm looking for a bit of guidance from the SO community on what best practise is and to see if there are other solutions out there.

Question:

Should I push these png files to the git repo? or is there a better way?