I am having the same issue.
Did you ever figure it out?
I have concluded that it is a false positive.
“There are some WordPress security plugins which will alert you if the contents of one of your plugin files changes (e.g. WordFence). This is a useful service – if unexpected changes occur, then it might mean that your site was hacked.
Unfortunately, WordFence uses a faulty algorithm to detect this, which results in lots of false positives.
The right way to perform this check would be by comparing your installed plugin with the plugin that was originally downloaded. However, WordFence instead compares your installed plugin with the plugin that can be downloaded today.”
