[mod] searx/locales.py: language names based on Unicode CLDR

rename "oc" to "Occitan":
* https://github.com/unicode-org/cldr/blob/35.1/seed/main/oc.xml#L115
* https://oc.wikipedia.org/wiki/Occitan

see https://github.com/searxng/searxng/pull/247#issuecomment-892382001

searx/locales.py

@@ -11,9 +11,7 @@ import pathlib
 from babel import Locale
 
 LOCALE_NAMES = {
-    "ar": "العَرَبِيَّة (Arabic)",
-    "fil": "Wikang Filipino (Filipino)",
-    "oc": "Lenga D'òc (Occitan)",
+    "oc": "Occitan",
     "nl_BE": "Vlaams (Dutch, Belgium)",
 }
 """Mapping of locales and their description.  Locales e.g. 'fr' or 'pt_BR'