Add support for Ubuntu 22.04, Fedora 36, EL 9, openSUSE 15.4

[pstorz]

This PR enables building for Ubuntu 22.04, Fedora 36, EL 9, openSUSE 15.4.
Removing support for obsolete openSUSE 15.2 and Fedora 34.

Please check

• Short description and the purpose of this PR is present above this paragraph
• Your name is present in the AUTHORS file (optional)

If you have any questions or problems, please give a comment in the PR.

Helpful documentation and best practices

• Git Workflow
• Automatic Sourcecode Formatting
• Check your commit messages

Checklist for the reviewer of the PR (will be processed by the Bareos team)

General

• PR name is meaningful
• Purpose of the PR is understood
• Separate commit for this PR in the CHANGELOG.md, PR number referenced is same
• Commit descriptions are understandable and well formatted

Source code quality

• Source code changes are understandable
• Variable and function names are meaningful
• Code comments are correct (logically and spelling)
• Required documentation changes are present and part of the PR
• bareos-check-sources --since-merge does not report any problems
• git status should not report modifications in the source tree after building and testing

Tests

• Tests are runs on new platform

[bruno-at-bareos]

Mostly okay, see proposal for the suse gcc block in spec.

[bruno-at-bareos]

During the review, the check-sources return modification on

Plugin 'fix copyright year' would modify 'core/cmake/BareosFindAllLibraries.cmake'
Plugin 'fix copyright year' would modify 'core/src/droplet/libdroplet/CMakeLists.txt'
Plugin 'clang-format check' would modify 'core/src/droplet/libdroplet/include/droplet/cdmi/crcmodel.h'
Plugin 'cmake format' would modify 'core/src/lib/CMakeLists.txt'

Once it build again and goes green, it will be time to bundle the commit, and add a changelog line.

[bruno-at-bareos]

After last green, the PR is ready to be merged. Thanks for the work.