Meets #14375: Footer is not fixed at the bottom after opening a taskboard

[``* `#14375` Footer is not fixed at the bottom after opening a taskboard``](https://www.openproject.org/work_packages/14375)
The weird padding was added in order to allow for enough space for menus and context menus outside of the html flow. So reducing the padding will make those overlap the footer and eventually disappear into the void.