Do not discard proxy_options that have been set when auto is specified

src/transports/http.c

@@ -575,6 +575,9 @@ static int apply_proxy_config(http_subtransport *t)
 		if ((error = git_remote__get_http_proxy(t->owner->owner, !!t->connection_data.use_ssl, &url)) < 0)
 			return error;
 
+		opts.credentials = t->owner->proxy.credentials;
+		opts.certificate_check = t->owner->proxy.certificate_check;
+		opts.payload = t->owner->proxy.payload;
 		opts.type = GIT_PROXY_SPECIFIED;
 		opts.url = url;
 		error = git_stream_set_proxy(t->io, &opts);