[mod] engines: remove uses of enable_http2 = False

This has only been needed because we were flagged by HTTP2 fingerprinting.
Now, since we use curl cffi, we can bypass the fingerpinting, so we can
use HTTP2 just fine without getting blocked.

searx/engines/uxwing.py

@@ -17,12 +17,10 @@ about = {
 categories = ['images', 'icons']
 
 base_url = "https://uxwing.com"
-enable_http2 = False
 
 
 def request(query, params):
     params['url'] = f"{base_url}/?s={quote_plus(query)}"
-    return params
 
 
 def response(resp):