heptapod-ci: also run tests for chg on python 2 I am not aware of any regular effort to run test with chg. So let's at least do it here. Differential Revision: https://phab.mercurial-scm.org/D8178

rust-dependencies: upgrade `micro-timer` dependency I wanted to to a tour of dependencies to upgrade, but only `micro-timer` has a new release which does not print when the function panics, which should be less misleading. Differential Revision: https://phab.mercurial-scm.org/D8605