feat: reduces group heading from h2 to h3

src/admin/components/forms/field-types/Group/index.scss

@@ -4,6 +4,7 @@
   margin-top: base(2);
   margin-bottom: base(2);
   display: flex;
+  position: relative;
 
   &__header {
     margin-bottom: base(1);

src/admin/components/forms/field-types/Group/index.tsx

@@ -47,7 +47,7 @@ const Group: React.FC<Props> = (props) => {
         {(label || description) && (
           <header className={`${baseClass}__header`}>
             {label && (
-              <h2 className={`${baseClass}__title`}>{label}</h2>
+              <h3 className={`${baseClass}__title`}>{label}</h3>
             )}
             <FieldDescription
               value={null}