fix(button): set user-select to none to make btn text not selectable

.changeset/tiny-eyes-burn.md

@@ -0,0 +1,5 @@
+---
+'@lion/button': patch
+---
+
+Set user-select to none on button, so that the inner text is not selectable.

packages/button/src/LionButton.js

@@ -61,6 +61,7 @@ export class LionButton extends DisabledWithTabIndexMixin(SlotMixin(LitElement))
           padding: 8px; /* padding to fix with min-height */
           outline: none; /* focus style handled below */
           cursor: default; /* /* we should always see the default arrow, never a caret */
+          user-select: none;
         }
 
         :host::before {