Centralize the collection of the HOSTNAME and DOMAINAME so that it's predictable and uniform across the various scripts (using the helper). Ensure it supports the various configurations users can have (both subdomain and without subdomain, override and no override).
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* using _obtain_hostname_and_domainname helper + covers when not a subdomain
doc: OVERRIDE_HOSTNAME takes priority
* added tests for non-subdomain hostname + further improvements
* moved SRS DOMAINANME tests into hostname test file + Allowing DOMAINNAME ENV to override what would be automatically set
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Co-authored-by: Georg Lauterbach <44545919+georglauterbach@users.noreply.github.com>
