fix border color on header

Author: langermank

packages/react/src/ActionList/Group.tsx

@@ -97,7 +97,7 @@ export const Group: React.FC<React.PropsWithChildren<ActionListGroupProps>> = ({
           // because the heading is hidden from the accessibility tree and only used for presentation role.
           // We will instead use aria-label to label the list. See a line below.
           aria-labelledby={listRole ? undefined : groupHeadingId}
-          aria-label={listRole ? (title ?? (slots.groupHeading?.props.children as string)) : undefined}
+          aria-label={listRole ? title ?? (slots.groupHeading?.props.children as string) : undefined}
           role={role || (listRole && 'group')}
         >
           {slots.groupHeading ? childrenWithoutSlots : props.children}
@@ -164,7 +164,7 @@ export const GroupHeading: React.FC<React.PropsWithChildren<ActionListGroupHeadi
       marginBottom: 2,
       borderTop: '1px solid',
       borderBottom: '1px solid',
-      borderColor: 'neutral.muted',
+      borderColor: 'var(--borderColor-muted)',
     }),
 
     [`.ActionListGroupHeading`]: {