fix: add no notifications message to fluent

Author: wash2

cosmic-applet-notifications/i18n/en/cosmic_applet_notifications.ftl

@@ -10,3 +10,4 @@ show-more = Show {$more} More
 clear-all = Clear All Notifications
 do-not-disturb = Do Not Disturb
 notification-settings = Notification Settings...
+no-notifications = No Notifications

cosmic-applet-notifications/src/main.rs

@@ -344,8 +344,11 @@ impl Application for Notifications {
 
             let notifications = if self.cards.is_empty() {
                 row![container(
-                    column![text_icon(&self.icon_name, 40), "No Notifications"]
-                        .align_items(Alignment::Center)
+                    column![
+                        text_icon(&self.icon_name, 40),
+                        text(&fl!("no-notifications"))
+                    ]
+                    .align_items(Alignment::Center)
                 )
                 .width(Length::Fill)
                 .align_x(Horizontal::Center)]