Submit button for category selection

[pfeuffer]

Proposed changes

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Your checklist for this pull request

Put an x in the boxes that apply. You can also fill these out after creating the PR. If you're unsure about any of them, don't hesitate to ask. We're here to help! This is simply a reminder of what we are going to look for before merging your code.

Contributor:

• PR is well described and the description can be used as a commit message on squash
• Changelog entry file created in gradle/changelog or CHANGELOG.md is updated for plugins
• Feature has been tested with different permissions
• Documentation updated (only necessary for new features or changed behaviour)

Reviewer:

• The clean code principles are respected (CleanCode)
• All new code/logic is implemented on the right spot / "Should this be done here?"
• UI changes fits into the layout
• The UI views / components are responsive (mobile views)
• Correct translations are available

Checklist for branch merge request (not required for forks)

• Branch is green/blue on Jenkins
• Quality Gate passed on SonarQube