[$] Debian's AWKward essential set

The Debian project has the concept of essentialpackages, which provide the bare minimum functionality consideredabsolutely necessary (or "essential") for a system tofunction. Packages tagged as essential, and the packages that arerequired by the set of essential packages, are always installed aspart of a Debian system. However, Debian's packaging rules do notrequire developers to explicitly declare dependencies on that set ofpackages (the essential set) but they can simply rely on the fact that thosewill always be present. That means that changing the essential set, asthe project may wish to do occasionally, is more complicated than itshould be. This came to light recently when a Debian developer askedwhat might be required to remove mawk to slim downthe project's container images.