checker: show files includes woff2

We show the files by processing the files, compressing them and then
listing all .gz files. However .woff2 isn't compress and is filtered
out. This change explictily includes .woff2 files in the list.

cmd/checker/main.go

@@ -212,7 +212,7 @@ func filewalker(basedir string, files *[]string) filepath.WalkFunc {
 			return errors.Wrap(err, "failed to walk fs")
 		}
 		ext := filepath.Ext(path)
-		if ext == ".gz" {
+		if ext == ".gz" || ext == ".woff2" {
 			path = strings.ReplaceAll(path, ".gz", "")
 			path = strings.ReplaceAll(path, basedir+"/", "")
 			*files = append(*files, path)