[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/stocksnap.py

@@ -21,8 +21,6 @@ about = {
     "require_api_key": False,
     "results": "JSON",
 }
-# otherwise all requests get blocked, probably HTTP2 fingerprinting
-enable_http2 = False
 
 base_url = "https://stocksnap.io"
 cdn_url = "https://cdn.stocksnap.io"