SRE-3459: add image_version and modify target_stash

[osalyk]

No description provided.

[ryon-jensen]

I don't know groovy that well, but I think looks good to me ... might just want to get rid of the printlns

[JohnMalmberg]

I think we need to find a way to store this information in the DAOS repository. Pipeline Lib should not be containing mappings of releases to target versions.

[janekmi]

There are still some problems with building release/2.6 on EL9.

Ref: https://jenkins-3.daos.hpc.amslabs.hpecorp.net/job/daos-stack/job/daos/job/ci-daos-stack-pipeline-lib-PR-488-release-2.6/27/pipeline-overview/?selected-node=271

[janekmi]

Build release/2.6 on EL9.7

BuildRequired: ofi needs to be built, use --build-deps=yes:
  File "/builddir/build/BUILD/daos-2.6.4/SConstruct", line 504:
    scons()
  File "/builddir/build/BUILD/daos-2.6.4/SConstruct", line 443:
    prereqs.run_build(opts)
  File "/builddir/build/BUILD/daos-2.6.4/site_scons/prereq_tools/base.py", line 559:
    self.__env.Clone().require(comp)
  File "/usr/lib/python3.9/site-packages/SCons/Util/envs.py", line 242:
    return self.method(*nargs, **kwargs)
  File "/builddir/build/BUILD/daos-2.6.4/site_scons/prereq_tools/base.py", line 809:
    raise error
  File "/builddir/build/BUILD/daos-2.6.4/site_scons/prereq_tools/base.py", line 799:
    if comp_def.build(env, needed_libs):
  File "/builddir/build/BUILD/daos-2.6.4/site_scons/prereq_tools/base.py", line 1450:
    raise BuildRequired(self.name)

Ref: https://jenkins-3.daos.hpc.amslabs.hpecorp.net/job/daos-stack/job/daos/job/ci-daos-stack-pipeline-lib-PR-488-release-2.6/27/artifact/artifacts/el9/build.log

[JohnMalmberg]

Missing tests appear to be intentionally not run and not applicable to this PR.