Fix for vips intervention image backend

The vips intervetion image backend isn't working right now, because InterventionBackend unlinks the temporary file too early. It is removed before the actual libvips commands are run against it, which makes them fail. The temporary file is removed in the destructor of InterventionBackend anyway, so this section is unnecessary.

src/InterventionBackend.php

@@ -293,9 +293,6 @@ public function getImageResource()
             if ($error) {
                 $this->markFailed($hash, $variant, $error);
             }
-            if (isset($path) && file_exists($path)) {
-                unlink($path);
-            }
         }
         return null;
     }