Draft: GCalWeekView: Apply correct left / right padding to hour label
The left / right padding was added at a time when the value as defined in Adwaita.css of the padding was not yet available. Hence padding was set to 0 then.
The fix applies it to the position where the labels get effectively added.
Removed unneccessary method update_hours_sidebar_size since it has no effect. Added initial width for the hours sidebar to gcal-week-view.ui