Converted 8 buttons, fixed a few bugs with markdown editor, added some testing for template logic. The fixes are not auto-testable within reasonable effort and the changes like button conversion have nothing specific to be tested for.
### Convert form buttons to new buttons
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### Justify "Delete release" button away from other buttons
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### Fix markdown editor on mobile
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### Buttons preview on mobile
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Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/9940
Reviewed-by: Gusted <gusted@noreply.codeberg.org>