Chore: General notification reformatting (#3182)

- I unified where in file the name of `NotificationProvider.name` is placed
- I made sure that all the providers adhere to the signature of `NotificationProvider.send()`
- I made sure that all the providers use `okMsg` if returning success messages directly from the function.
  Here a discussion should be had:
  Should this be refactored into a constant of `NotificationProvider`? I could imagine that `NotificationProvider.SENDING_SUCCESSFULL`  could be a suitable alternative.
- I made sure all providers have the URL they `POST`/`GET` to be extraced into a variable.
  => refactored this way due to Nelsons suggestion

server/notification-providers/bark.js

@@ -46,29 +46,29 @@ class Bark extends NotificationProvider {
     }
 
     /**
-     * Add additional parameter for Bark v1 endpoints
+     * Add additional parameter for Bark v1 endpoints.
+     * Leads to better on device styles (iOS 15 optimized)
      * @param {BeanModel} notification Notification to send
-     * @param {string} postUrl URL to append parameters to
      * @returns {string} Additional URL parameters
      */
-    appendAdditionalParameters(notification, postUrl) {
+    additionalParameters(notification) {
         // set icon to uptime kuma icon, 11kb should be fine
-        postUrl += "?icon=" + barkNotificationAvatar;
+        let params = "?icon=" + barkNotificationAvatar;
         // grouping all our notifications
         if (notification.barkGroup != null) {
-            postUrl += "&group=" + notification.barkGroup;
+            params += "&group=" + notification.barkGroup;
         } else {
             // default name
-            postUrl += "&group=" + "UptimeKuma";
+            params += "&group=" + "UptimeKuma";
         }
         // picked a sound, this should follow system's mute status when arrival
         if (notification.barkSound != null) {
-            postUrl += "&sound=" + notification.barkSound;
+            params += "&sound=" + notification.barkSound;
         } else {
             // default sound
-            postUrl += "&sound=" + "telegraph";
+            params += "&sound=" + "telegraph";
         }
-        return postUrl;
+        return params;
     }
 
     /**
@@ -100,9 +100,8 @@ class Bark extends NotificationProvider {
             // url encode title and subtitle
             title = encodeURIComponent(title);
             subtitle = encodeURIComponent(subtitle);
-            let postUrl = endpoint + "/" + title + "/" + subtitle;
-            postUrl = this.appendAdditionalParameters(notification, postUrl);
-            result = await axios.get(postUrl);
+            const params = this.additionalParameters(notification);
+            result = await axios.get(`${endpoint}/${title}/${subtitle}${params}`);
         } else {
             result = await axios.post(`${endpoint}/push`, {
                 title,