This logic is checking if package.packageUriRoot directory exists, so the lib directory.

flutter/packages#1951 removed this directory flutter_template_images

Removes the empty Dart file, which used to be required by pub.dev checks but no longer is.

But because the lib doesn't exist, on every run it thinks the pub dependencies are out of date, and pub get needs to be run.

Either that directory is needed, or the tool needs to be updated.

See #107873 (comment)