Fix "Copied" box not showing up when copying any password

Fixes https://github.com/lesspass/lesspass/issues/446

packages/lesspass-pure/src/services/tooltip.js

@@ -1,11 +1,11 @@
 export function showTooltip(element, message, position = "right") {
-  element.setAttribute("data-balloon", message);
+  element.setAttribute("aria-label", message);
   element.setAttribute("data-balloon-visible", "");
   element.setAttribute("data-balloon-pos", position);
 }
 
 export function hideTooltip(element) {
-  element.removeAttribute("data-balloon");
+  element.removeAttribute("aria-label");
   element.removeAttribute("data-balloon-visible");
   element.removeAttribute("data-balloon-pos");
 }