Switch from gzip compression to xz compression for packages

Summary

Chef omnibus defaults to using gzip compression for deb and rpm packages, but support xz compression. We should switch to XZ compression.

Proposal

1. Confirm that our supported distros will all support xz compressed debs and rpms
2. Update the compressor_type used in debs and rpms in https://gitlab.com/gitlab-org/omnibus-gitlab/-/blob/master/config/projects/gitlab.rb
3. Try to determine how much extra time xz compression is adding to our builds vs gzip

References

Prior investigation shows this should provide about a 19% decrease in package size: #6292 (comment 669691295)