Sort ascending `$grid-breakpoints` and `$container-max-widths` maps

Created by: iamandrewluca

Extend $grid-breakpoints and $container-max-widths maps, as $theme-colors see #26714

When extending $grid-breakpoints and $container-max-widths we must be sure that they are sorted ascending, added a new function that sorts maps by their values. Now _assert-ascending call it seems to be obsolete if we sort maps before that

If user extends mentioned vars after variables import map-sort-by-values must be called again to be sure they are sorted