Prepare epel & crb for image mode; improved guest cleanup; Jira Cloud support; hardware preset specification; rhel-6 adjustments

What's Changed

• Refresh the linkcheck cache everyday by @LecrisUT in #4858
• Fix variable used in string dictionary normalization error by @happz in #4842
• Fix how plan/guest ansible key is displayed by @happz in #4419
• Update GitHub Actions by @renovate[bot] in #4821
• Add missing imports by @happz in #4843
• Add proper Command.__iadd__ method to correctly support += operator by @happz in #4844
• Adjust flaky /tests/plan/import/basic test by @psss in #4882
• Use Optional instead of | None by @happz in #4845
• Remove a rhel8 workaround in pytest by @LecrisUT in #4596
• Set /bin/dmesg as essential-requires for dmesg plugin by @tcornell-bus in #4881
• Fix dummy messages of specification error in hardware requirement parser by @happz in #4846
• Move config-manager install to package manager abstraction by @thrix in #4848
• Add Ubuntu development dependencies by @happz in #4728
• Cleanup step should apply to all guests, even not ready ones by @happz in #4866
• Do not mangle shebangs on helper scripts by @bgoncalv in #4874
• Update jira integration to use Jira Cloud by @psss in #4880
• Running tmt clean will now show disk space freed by @AthreyVinay in #4801
• Remove redundant install_* methods by @AthreyVinay in #4792
• Add generic tmt context to AGENTS.md by @happz in #4585
• Reference output.txt in results.yaml when custom results are missing by @bajertom in #4888
• Avoid ARG_MAX overflow in bootc image-mode builds by @Lorquas in #4793
• Add web-link field to Result for browsable test links by @kamaxeon in #4878
• Add enable_repo() and disable_repo() to package manager abstraction by @thrix in #4903
• Specification for reusable hardware configurations by @AthreyVinay in #4833
• Support epel and crb features in Image Mode by @thrix in #4800
• Release 1.74.0 by @psss in #4911

New Contributors

• @bgoncalv made their first contribution in #4874
• @kamaxeon made their first contribution in #4878

Full Changelog: 1.73.0...1.74.0