feat(ui): update button variants following figma (#482)

* feat(ui): update button variants following figma

* feat(ui): separate size prop to allow for regular and small sized button variants

* update type to no longer include minimal-small

* update uno css config to use new spacing system

* add variants and sizes to file upload; update button and file upload stories

* add mini button variant and update small button

* specify width on icon-only regular variant

* update plus buttons to be mini sizes

* remove redundant classnames

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Co-authored-by: doprz <52579214+doprz@users.noreply.github.com>

src/views/components/calendar/CalendarBottomBar.tsx

@@ -60,12 +60,12 @@ export default function CalendarBottomBar({ courseCells, setCourse }: CalendarBo
             </div>
             <div className='flex items-center screenshot:hidden'>
                 {displayCourses && <Divider orientation='vertical' size='1rem' className='mx-1.25' />}
-                <Button variant='single' color='ut-black' icon={CalendarDots} onClick={saveAsCal}>
+                <Button variant='minimal' color='ut-black' icon={CalendarDots} onClick={saveAsCal}>
                     Save as .CAL
                 </Button>
                 <Divider orientation='vertical' size='1rem' className='mx-1.25' />
                 <Button
-                    variant='single'
+                    variant='minimal'
                     color='ut-black'
                     icon={ImageSquare}
                     onClick={() => requestAnimationFrame(() => saveCalAsPng())}