Add a min-height: 1.5rem; to custom controls
Add a min-height: 1.5rem; to custom controls

Fixes #20730.

This change computes the minimum needed height of what a single line of text would be for the custom checkboxes/radios. This is required because our custom control indicators are positioned absolutely, meaning they cannot be clearfixed or anything like that. Using a computed value means it should scale nicely in case of customization

twbs/bootstrap,sealocal/bootstrap,hebbet/bootstrap,copperdesign/bootstrap,creativewebjp/bootstrap,lemuelbarango/bootstrap,9-chirno/chirno,hebbet/bootstrap,gijsbotje/bootstrap,nice-fungal/bootstrap,Hemphill/bootstrap-docs,SweetProcess/bootstrap,lipis/bootstrap,peterblazejewicz/bootstrap,IdanCo/bootstrap,zalog/bootstrap,NCARB/bootstrap,9-chirno/chirno,edanbarak/bootstrap,joblocal/bootstrap,9-chirno/chirno,Delagen/bootstrap,fschumann1211/bootstrap,janseliger/bootstrap,twbs/bootstrap,johnajacob/bootstrap,tomlutzenberger/bootstrap,tjkohli/bootstrap,lemuelbarango/bootstrap,copperdesign/bootstrap,GerHobbelt/bootstrap,jipexu/bootstrap,realcrowd/bootstrap,slavanga/bootstrap,bootstrapbrasil/bootstrap,yuyokk/bootstrap,hebbet/bootstrap,jipexu/bootstrap,Lyricalz/bootstrap,yuyokk/bootstrap,tibo66/bootstrap,TheFridayInstitute/bootstrap,IdanCo/bootstrap,TheFridayInstitute/bootstrap,realcrowd/bootstrap,johnajacob/bootstrap,Scoutski/bootstrap,fschumann1211/bootstrap,bootstrapbrasil/bootstrap,seanwu99/bootstrap,JumpLinkNetwork/bootstrap-backward,xt0rted/bootstrap,slavanga/bootstrap,xt0rted/bootstrap,yuyokk/bootstrap,johnajacob/bootstrap,bardiharborow/bootstrap,kvlsrg/bootstrap,Lyricalz/bootstrap,nice-fungal/bootstrap,tjkohli/bootstrap,davethegr8/bootstrap,kvlsrg/bootstrap,fschumann1211/bootstrap,Scoutski/bootstrap,Hemphill/bootstrap-docs,TheFridayInstitute/bootstrap,seanwu99/bootstrap,GerHobbelt/bootstrap,tagliala/bootstrap,SweetProcess/bootstrap,igoynawamreh/bootstrap,supergibbs/bootstrap,vsn4ik/bootstrap,andresgalante/bootstrap,xt0rted/bootstrap,bardiharborow/bootstrap,bardiharborow/bootstrap,igoynawamreh/bootstrap,lipis/bootstrap,vsn4ik/bootstrap,realcrowd/bootstrap,inway/bootstrap,janseliger/bootstrap,NCARB/bootstrap,n054/bootstrap,afuno/bootstrap,jipexu/bootstrap,andresgalante/bootstrap,Delagen/bootstrap,coliff/bootstrap,Lyricalz/bootstrap,slavanga/bootstrap,abvalentine/bootstrap,Lyricalz/bootstrap,n054/bootstrap,m5o/bootstrap,peterblazejewicz/bootstrap,edanbarak/bootstrap,stanwmusic/bootstrap,tagliala/bootstrap,tibo66/bootstrap,edanbarak/bootstrap,supergibbs/bootstrap,lipis/bootstrap,n054/bootstrap,JumpLinkNetwork/bootstrap-backward,stanwmusic/bootstrap,inway/bootstrap,GerHobbelt/bootstrap,igoynawamreh/bootstrap,davethegr8/bootstrap,davethegr8/bootstrap,JumpLinkNetwork/bootstrap-backward,gijsbotje/bootstrap,seanwu99/bootstrap,seanwu99/bootstrap,tibo66/bootstrap,afuno/bootstrap,janseliger/bootstrap,copperdesign/bootstrap,jipexu/bootstrap,lemuelbarango/bootstrap,IdanCo/bootstrap,creativewebjp/bootstrap,tomlutzenberger/bootstrap,andresgalante/bootstrap,abvalentine/bootstrap,slavanga/bootstrap,9-chirno/chirno,abvalentine/bootstrap,peterblazejewicz/bootstrap,copperdesign/bootstrap,bardiharborow/bootstrap,vsn4ik/bootstrap,realcrowd/bootstrap,sealocal/bootstrap,joblocal/bootstrap,NCARB/bootstrap,supergibbs/bootstrap,tomlutzenberger/bootstrap,bootstrapbrasil/bootstrap,edanbarak/bootstrap,andresgalante/bootstrap,fschumann1211/bootstrap,afuno/bootstrap,tibo66/bootstrap,afuno/bootstrap,JumpLinkNetwork/bootstrap-backward,vsn4ik/bootstrap,NCARB/bootstrap,sealocal/bootstrap,yuyokk/bootstrap,Delagen/bootstrap,lemuelbarango/bootstrap,kvlsrg/bootstrap,joblocal/bootstrap,Delagen/bootstrap,davethegr8/bootstrap,abvalentine/bootstrap,Hemphill/bootstrap-docs,SweetProcess/bootstrap,Scoutski/bootstrap,supergibbs/bootstrap,creativewebjp/bootstrap,stanwmusic/bootstrap,SweetProcess/bootstrap,tagliala/bootstrap,lipis/bootstrap,zalog/bootstrap,hebbet/bootstrap,Hemphill/bootstrap-docs,coliff/bootstrap,sealocal/bootstrap,joblocal/bootstrap,inway/bootstrap,nice-fungal/bootstrap,gijsbotje/bootstrap,m5o/bootstrap,xt0rted/bootstrap,igoynawamreh/bootstrap,TheFridayInstitute/bootstrap,janseliger/bootstrap,johnajacob/bootstrap,Scoutski/bootstrap,IdanCo/bootstrap,zalog/bootstrap,creativewebjp/bootstrap,stanwmusic/bootstrap,gijsbotje/bootstrap,n054/bootstrap