Invenio-theme-tugraz

- ui: add banner to header

- translation: fix typo

- fix: error_handler gets 1 parameter

- ui: add 423 error page
- fix: types could be empty list
- setup: sort tests imports
- workflows: change to reusable workflows
- wording: update one string frontpage
- wording: update frontpage

- wording: update text in benefits
- translation: fix research result typo
- ui: remove commented code
- ui: remove comingsoon rule