Update NavList to use the new GroupHeading API and add an as prop to specify the heading level (h3 to match with the default) (#4593)

* Add the default heading level with the as prop for NAvlist.Group

* Create calm-insects-boil.md

* update the comment

Author: broccolinisoup

.changeset/calm-insects-boil.md

@@ -0,0 +1,5 @@
+---
+"@primer/react": patch
+---
+
+Update NavList to use the new ActionList.GroupHeading API and Add an "as" prop to specify the heading level as default h3. (No changes expected in the rendered HTML)

packages/react/src/NavList/NavList.tsx

@@ -259,7 +259,9 @@ const Group: React.FC<NavListGroupProps> = ({title, children, sx: sxProp = defau
     <>
       {/* Hide divider if the group is the first item in the list */}
       <ActionList.Divider sx={{'&:first-child': {display: 'none'}}} />
-      <ActionList.Group {...props} title={title} sx={sxProp}>
+      <ActionList.Group {...props} sx={sxProp}>
+        {/* Setting up the default value for the heading level. TODO: API update to give flexibility to NavList.Group title's heading level */}
+        <ActionList.GroupHeading as="h3">{title}</ActionList.GroupHeading>
         {children}
       </ActionList.Group>
     </>