Removes unused files and artefacts from the source tree.

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• Short description and the purpose of this PR is present above this paragraph
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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
• Commit descriptions are understandable and well formatted
• Is the PR title usable as CHANGELOG entry?
• Separate commit for CHANGELOG.md ("update CHANGELOG.md"). The PR number is correct.

Source code quality

• Source code changes are understandable
• bareos-check-sources --since-merge does not report any problems