We have tests that manually unpackage the RPM and Debian package
distributions and start a cluster manually (not from the service) and
run a basic suite of integration tests against them. This is problematic
because it is not how the packages are intended to be used (instead,
they are intended to be installed using the package installation tools,
and started as services) and so violates assumptions that we make about
directory paths. This commit removes these integration tests, instead
relying on the packaging tests to ensure the packages are not
broken. Additionally, we add a sanity check that the package
distributions can be unpackaged. Finally, with this change we can remove
some leniency from elasticsearch-env about checking for the existence of
the environment file which the leniency was there solely for these
integration tests.
Relates #27725
cd474df972