adjust styling of settings' subheadings (fix #8176)
adjust styling of settings' subheadings (fix #8176)

cgeo/cgeo,S-Bartfast/cgeo,rsudev/c-geo-opensource,rsudev/c-geo-opensource,tobiasge/cgeo,cgeo/cgeo,S-Bartfast/cgeo,tobiasge/cgeo,auricgoldfinger/cgeo,auricgoldfinger/cgeo,S-Bartfast/cgeo,matej116/cgeo,cgeo/cgeo,matej116/cgeo,auricgoldfinger/cgeo,tobiasge/cgeo,cgeo/cgeo,rsudev/c-geo-opensource,matej116/cgeo