Closes #32 - Implementation of Github Action that generates the release changelog how it was previously done

[danipaniii]

Implementation of Github Action that generates the release how it was previously done.

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This change is 

[heiko-holz]

Reviewed 3 of 3 files at r1, 1 of 1 files at r2, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @danipaniii)

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.github/workflows/eumserver_release.yml line 46 at r1 (raw file):

            sinceTag: ${{ steps.previoustag.outputs.tag }} 
            dateFormat: 
            maxIssues: 500

we need to watch if we exceed the secondary rate limit for GitHub API request once we apply this to the Ocelot Agent repo

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.github/workflows/eumserver_release.yml line 47 at r1 (raw file):

            dateFormat: 
            maxIssues: 500
            unreleased: false

do you know by chance what this actually means?
The docu says "Add to log unreleased closed issues.", but what are unreleased closed issues?
Issues that are not connected to any PR but were closed in the respective time frame?

Code quote:

heinrichreimer/github-changelog-generator-action

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.github/workflows/eumserver_release.yml line 57 at r1 (raw file):

            body: ${{ steps.build_changelog.outputs.changelog }}
            files: artifacts/*
            generate_release_notes: false

did this ever work?

Code quote:

softprops/action-gh-release

[quandor]

Reviewed all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @danipaniii)

[quandor]

Reviewed 2 of 3 files at r1, 1 of 1 files at r2.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @danipaniii)