Initial EL9 support

[ekohl]

Currently CentOS Stream 9 is being built. This changes things so EL8 and EL9 are treated the same. Both use systemd and chrony.

[codecov]

Codecov Report

Merging #1719 (e0296ea) into master (3c32c5b) will not change coverage.
The diff coverage is 100.00%.

❗ Current head e0296ea differs from pull request most recent head df7250e. Consider uploading reports for the commit df7250e to get more accurate results

@@           Coverage Diff           @@
##           master    #1719   +/-   ##
=======================================
  Coverage   74.64%   74.64%           
=======================================
  Files          82       82           
  Lines        4863     4863           
=======================================
  Hits         3630     3630           
  Misses       1233     1233           

Impacted Files	Coverage Δ
lib/beaker/host_prebuilt_steps.rb	73.31% <100.00%> (ø)

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[ekohl]

@trevor-vaughan mind taking a look?

[bastelfreak]

@trevor-vaughan can you take a look?

[GabrielNagy]

This looks good from our end 👍