Apply a handful of changes to reduce the diff between the two:
* Cancel running jobs on new pushes
* Enable log color and backtraces
* Add timeouts
* Specify CI runner versions
* Add an armv7 job
* Replace the name NO_STD with BUILD_ONLY
* Update the extension to the canonical .yaml
* Set AR_ and CC_ environments in docker
* Install requirements to build MPFR
Instead use the Cargo runner feature. The binfmt_misc approach requires running a privileged
container for setup. Not all docker setups support privileged containers so the test suite should be
more accessible with this change as no privileged container is needed.
`apt update` and `apt install` should be in the same Docker RUN statement, otherwise `apt update` will be cached and `apt install` will 404 if a package no longer exists.