Fix height of some dialogs

* fix #36641: Style/General window too large
* adjust the height of 2 more dialogs to fit on netbook screens (1024x600)

a better and permanent solution might be needed...

Qt Creator on Windows thinks the smallest possible sizes to be:
* editstyle.ui: 770x610 (changed from 1148x738 to to 904x577 in this PR, because that is what it was before a52827e)
* editstaff.ui: 613x596 (changed from 920x656 to 920x577 in this PR)
* textproperties.ui: 485x454 (changed from 647x664 to 647x577 in this PR)