searx/data/engines_languages.json: sort json file (no content change)

To get meaningfull diffs, the json file has to be sorted.  Before applying any
further content patch, the json file needs a inital sort (without changing any
content).

Sorted by::

  import sys, json

  with open('engines_languages.json') as f:
      j = json.load(f)

  with open('engines_languages.json', 'w') as f:
      json.dump(j, f, indent=2, sort_keys=True)

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>