Fix pipeline: versioning without proprietary gh-action

[stefancyliax]

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Fix for the currently failing pipeline. For an unknown reason the gh-action step of replacing the versioning in the main mapping file fails. The fix removes the proprietary gh-action step with a simple 'sed' command with does the same thing.

Pipeline is fixed with this change. There are no regressions.

Check the checklist

• I have performed a self-review of my own code/documentation.
• [ ] My documentation changes are related to another repository in the organization. Here is the link to the issue/repo.
• My changes generate no new warnings during the documentation generation.
• The existing ci which pushes the documentation to gh-pages passes with my changes.