Nowadays, GNATformat is part of GNAT, so just having an explicit build
of GNAT with the `--smart-rebuild` anod option and `gnatformat-edge` in
`anod vcs` is enough to trigger its build.
Note that since GNATformat has been stabilized, its build on the safe
track does *not* use the Libadalang wavefront, making the current
duplicated build useless.
Since gnatformat build failures prevent Libdalang test machines from
booting, it makes sense to check that Libadalang/Langkit commits do not
break gnatformat's build.
The CB currently requests two builds: gnat and libadalang_for_customers,
each one with its own "anod build" shell command. With enough bad luck,
new components can be uploaded to Cathod in between, making the CB
build during the second step components that were already built during
the first step, making the CB timeout (the CB is already close to the
timeout limit).
Switch to an electrolyt plan instead, so that this kind of issue is less
likely to happen (the Anod scheduler/Cathod requests run only once).
