SearXNG does not allow a None value in the content field of a result item.
If the key (shortDescription, uploaderName) in the JSON response from piped
exists but is set to None, SearXNG ignores this result item::
DEBUG searx : result: invalid content: { .., 'content': None, ..}
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
