If HTTP/2 is unsupported by libcurl, force HTTP/1.1 This will prevent log flood, by printing log only in case of first request.
If HTTP/2 is unsupported by libcurl, force HTTP/1.1
This will prevent log flood, by printing log only in case of first request.

Tested by changing CURL_HTTP_VERSION_2_0 to invalid randum number
and sending in multiple requests at the same time, so new HTTP
session open would be needed.

aarond10/https_dns_proxy,aarond10/https_dns_proxy