Hi Dick,
Thanks for contacting us!
You can see the same difference in our public repository for the WordPress plugin if you click on “Load diff” for composer.lock at https://github.com/tinify/wordpress-plugin/commit/ae95c9b228531998f4a37423e9941b64409ebe98
However, yours is the other way around. What action did you take before you received this warning from Wordfence? Did you install an older version of the plugin? The change reflects one of the differences between the previous version of the plugin (3.2.1) and the current version (3.3), but it looks like you went from 3.3 to 3.2.1 (or an older release of the plugin).
In any case, from a security perspective, it is not something to worry about. The code is perfectly safe, you’re just using an older version of the library that handles the compressions.
If you’re still wondering why Wordfence is showing a warning for it then that would be something to ask the Wordfence team about.