http/h1_srequest: make sure we start tls when using a https proxy

Author: daurnimator

http/request.lua

@@ -454,6 +454,7 @@ function request_methods:go(timeout)
 				local old_url = self:to_uri(false)
 				host = assert(proxy.host, "proxy is missing host")
 				port = proxy.port or http_util.scheme_to_port[proxy.scheme]
+				tls = (proxy.scheme == "https")
 				-- proxy requests get a uri that includes host as their path
 				if not cloned_headers then
 					request_headers = request_headers:clone()