update onion engines to v3

remove not_evil which has been down for a while now:
https://old.reddit.com/r/onions/search/?q=not+evil&restrict_sr=on&t=year

searx/settings.yml

@@ -832,13 +832,6 @@ engines:
       require_api_key: false
       results: JSON
 
-  # Requires Tor
-  - name: not evil
-    engine: not_evil
-    categories: onions
-    enable_http: true
-    shortcut: ne
-
   - name: nyaa
     engine: nyaa
     shortcut: nt