go_1_11: add url to flaky test

+1
+1
pkgs/development/compilers/go/1.11.nix
··· 125 125 ./remove-fhs-test-references.patch 126 126 ./skip-external-network-tests.patch 127 127 ./skip-nohup-tests.patch 128 + # breaks under load: https://github.com/golang/go/issues/25628 128 129 ./skip-test-extra-files-on-386.patch 129 130 ]; 130 131