Clone button enhancements (#33362)

- Add box-shadow to default tippy theme
- Make colors for tabs match the ones from `.ui.tabular.menu`
- Remove tippy arrow and slightly offset tooltip closer to the button
- Fix setting of `aria-haspopup` when default role is used with tippy

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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

web_src/js/features/repo-common.ts

@@ -99,6 +99,7 @@ function initClonePanelButton(btn: HTMLButtonElement) {
     placement: 'bottom-end',
     interactive: true,
     hideOnClick: true,
+    arrow: false,
   });
 }