fix(tabs): add border-color transition for smoother animation (#1904)

Author: ze-flo

packages/tabs/src/styled/StyledTabList.ts

@@ -24,6 +24,7 @@ const colorStyles = ({ theme }: ThemeProps<DefaultTheme>) => {
   const foregroundColor = getColor({ theme, variable: 'foreground.default' });
 
   return css`
+    transition: border-color 0.25s ease-in-out;
     color-scheme: only ${p => p.theme.colors.base};
     border-bottom-color: ${borderColor};
     color: ${foregroundColor};