return array if null

Author: DirtyRacer1337

src/Support/FileRemover/DefaultFileRemover.php

@@ -63,7 +63,7 @@ public function removeFromConversionsDirectory(Media $media, string $disk): void
                 try {
                     $allFilePaths = $this->filesystem->disk($disk)->allFiles($directory);
 
-                    $conversions = array_keys($media->generated_conversions);
+                    $conversions = array_keys($media->generated_conversions ?? []);
 
                     $imagePaths = array_filter(
                         $allFilePaths,