change 'Duplicate' button to 'Clone' in gradient editor

Author: hvianna

public/index.html

@@ -819,7 +819,7 @@ <h2>Configuration</h2>
 			</div>
 			<div class="grid grid-2-cols gap-lg mt-1">
 				<button id="btn-export-gradient">Export</button>
-				<button id="btn-save-gradient-copy">Duplicate</button>
+				<button id="btn-save-gradient-copy">Clone</button>
 			</div>
 		</div>
 	</div> <!-- #gradient-editor -->