Automatically attach the required files to releases

[ColinHDev]

Summary of the discussion

As described in #1955, the Release workflow currently requires that an oeo-closure.owl file present in the build-files.zip artifact to be attached to a release. However that pull request would remove said file from the artifacts for a reduced completion time of workflow runs.

This Pr tries to automate the release workflow. Instead of a maintainer going to the workflow artifacts of two separate runs to download the build-files.zip and existing-terms-and-definitions.zip and create a release with them, the maintainer would now only have to write and publish the release and this workflow would then automatically attach said files.

However, I am not really able to test this easily. But even if the automation fails, this pr ensures that a version of build-files.zip is uploaded that contains the oeo-closure.zip file, so the maintainer can add it automatically.

Type of change (CHANGELOG.md)

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Workflow checklist

Automation

Closes #

PR-Assignee

• 🐙 Follow the Pull Request Workflow
• 📝 Update the CHANGELOG.md
• 📙 Add #'s to term tracker annotation

Reviewer

• 🐙 Follow the Reviewer Guide
• 🐙 Provided feedback and show sufficient appreciation for the work done

[stap-m]

@jh-RLI could you please also take a look at this PR?