fix: set translatable on show alert (#16427)

frappe/public/js/frappe/ui/theme_switcher.js

@@ -124,7 +124,7 @@ frappe.ui.ThemeSwitcher = class ThemeSwitcher {
 	toggle_theme(theme) {
 		this.current_theme = theme.toLowerCase();
 		document.documentElement.setAttribute("data-theme-mode", this.current_theme);
-		frappe.show_alert("Theme Changed", 3);
+		frappe.show_alert(__("Theme Changed"), 3);
 
 		frappe.xcall("frappe.core.doctype.user.user.switch_theme", {
 			theme: toTitle(theme)