Adding CI that can build into multiple bazel versions, right now focusing
on the latest of each of the LTS version

Making 6.5.0 the default bazel version

Our tests where using the old and deprecated bundled pkg_tar rule, now
we need to grab it from rules_pkg instead.

Adding the results of running buildifier over the files.

Turns out there's a prebuilt buildifier that speeds up things a lot by
not having to rebuild the binary on each checkout of the repository

We all know the joke of Bazel just got it's 1000+1 flag each time a new
feature gets released, the aspect.dev folks have condensed a few flags
that speed up things and make sure bazel is used in the right way, so
let's start adopting it.

bumping skylib so we can use the platforms repository properly now

Following conventions from other rules so that there's a directory that
can be entirely built from other workspaces with
`bazel build @bazeldnf//bazeldnf/...`. It should be self contained and
inject as many dependencies into the parent workspace as needed.

By providing a proper toolchain instead of an alias we remove the
dependency on rules_go when someone uses bazeldnf externally, but also
works better for cross compilation and other kind of processes

Now we provide an e2e test for bazel5 with no bzlmod, it shows the
minimal setup to consume from bazeldnf rules

make sure bazel6 repos can consume bazeldnf when bzlmod is off

adding one more e2e test for the rule