Update file_info.go (fix errcheck issue) (#28966)

Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>

server/i18n/en.json

@@ -5162,6 +5162,10 @@
     "id": "app.file_info.save.app_error",
     "translation": "Unable to save the file info."
   },
+  {
+    "id": "app.file_info.seek.gif.app_error",
+    "translation": "Unable to seek to the beginning of the GIF data."
+  },
   {
     "id": "app.file_info.set_searchable_content.app_error",
     "translation": "Unable to set the searchable content of the file."