Clipboard copy enhancements (#27669)

1. Do not show temporary tooltips that are triggered from within
dropdowns. Previously this resulted in the tooltip being stuck to
top-left of the page like seen on issue comment URL copy. I could not
figure out any tippy options that prevent this, so I think it's better
to just not show it.
1. Refactor `initGlobalCopyToClipboardListener` so that it does not run
a often useless `document.querySelector` on every click, make
`data-clipboard-text-type` work with `data-clipboard-target`. No use in
current code base but still good to have. Finally some minor code
cleanup in the function.

Point 1 is for this copy button:

<img width="229" alt="image"
src="81f34746-8ea5-43d9-8c6f-f6f417a9e4ad">

---------

Co-authored-by: Giteabot <teabot@gitea.io>

web_src/js/modules/tippy.js

@@ -169,6 +169,11 @@ export function initGlobalTooltips() {
 }
 
 export function showTemporaryTooltip(target, content) {
+  // if the target is inside a dropdown, don't show the tooltip because when the dropdown
+  // closes, the tippy would be pushed unsightly to the top-left of the screen like seen
+  // on the issue comment menu.
+  if (target.closest('.ui.dropdown > .menu')) return;
+
   const tippy = target._tippy ?? attachTooltip(target, content);
   tippy.setContent(content);
   if (!tippy.state.isShown) tippy.show();