* ansible-test: add Ubuntu 18.04 container (#50790) * ansible-test: Add Ubuntu 18.04 to Shippable CI nodes * re-add ubuntu1604/3 to matrix * forgot to add environment for git kill gpg-agent (cherry picked from commit828df4b336) * ansible-test: apt cleanup and futher 18.04 fixes (#50906) (cherry picked from commitbbad033a5e)