add support for jfif files

Author: imahmood

config/file-storage.php

@@ -16,6 +16,7 @@
             'formats' => [
                 'png' => 'jpg',
                 'webp' => 'jpg',
+                'jfif' => 'jpg',
                 'heic' => 'jpg',
             ],
         ],

src/functions.php

@@ -5,5 +5,5 @@
 
 function is_image(?string $filename): bool
 {
-    return $filename && preg_match('/\.(webp|heic|jpg|jpeg|png)$/i', $filename);
+    return $filename && preg_match('/\.(webp|heic|jfif|jpg|jpeg|png)$/i', $filename);
 }