SvgIcon: pass className to loader

app/soapbox/components/sidebar-navigation-link.tsx

@@ -39,8 +39,8 @@ const SidebarNavigationLink = ({ icon, text, to, count }: ISidebarNavigationLink
 
         <Icon
           src={icon}
-          size={20}
           className={classNames({
+            'h-5 w-5': true,
             'text-primary-700 dark:text-white': !isActive,
             'text-white': isActive,
           })}

app/soapbox/components/ui/icon/svg-icon.tsx

@@ -16,7 +16,7 @@ const SvgIcon = ({ src, alt, size = 24, className }: ISvgIcon): JSX.Element => (
     title={alt}
     width={size}
     height={size}
-    loader={<div style={{ width: size, height: size }} />}
+    loader={<svg className={className} width={size} height={size} />}
   />
 );