test: verify container upgrade

[troglobit]

Add test to verify container upgrade works as intended. Or, at the very least, test manually before each release.

Purpose is to check for regressions like:

• container upgrade no longer works #623

Note: this test likely need to be run manually, for now, because the bundled images are one of a kind (no multiple versions of the same container image), there is also no way for DUTs to connect to the Internet. The only reasonable way forward would be to bundle a newer (or older?) image in the Infamy container that the DUT can download. This can possibly also be solved by expanding on the general DUT upgrade framework (sharing a build/test host directory with Infamy).