Use Composition API to add/remove from composition (#5941)

* Use composition API in RemoveAction

* refactor: ScatterPlotView to use composition API

* fix: initialize transaction to null and reset

* fix: remove seriesKey and correct found condition

* refactor: Gauge to use composition API

* refactor: DisplayLayout to use composition API

* test: RemoveAction starts and ends transactions

* test: add ScatterPlot add/remove telemetry test

* test: fix e2e test and add annotation

* test: remove unnecessary awaits

* test: make some displayLayout tests stable

* test{displayLayout}: navigate to objects via url

* test(gauge): add test for add/remove telemetry

* fix(#3117): init layoutItems within transaction

* refactor: add clearSelection() method

* test: remove unstable tag

* fix(#3117): init frames and use transactions

- fixes #3117 for flexible layouts by syncing frames and composition

- also uses transactions now to avoid race condition

* test(flexibleLayout): removing items via context menu

- add test for removing items via context menu while focusing the layout

- add test for removing items via context menu while not focusing the layout

* fix(e2e): use pluginFixtures

* refactor(e2e): improve selectors

* refactor: use async/await for saving transactions

* docs(e2e): fix comments

* test: use soft expects

Co-authored-by: Jamie V <jamie.j.vigliotta@nasa.gov>

src/api/Editor.js

@@ -56,17 +56,12 @@ export default class Editor extends EventEmitter {
      * Save any unsaved changes from this editing session. This will
      * end the current transaction.
      */
-    save() {
+    async save() {
         const transaction = this.openmct.objects.getActiveTransaction();
-
-        return transaction.commit()
-            .then(() => {
-                this.editing = false;
-                this.emit('isEditing', false);
-                this.openmct.objects.endTransaction();
-            }).catch(error => {
-                throw error;
-            });
+        await transaction.commit();
+        this.editing = false;
+        this.emit('isEditing', false);
+        this.openmct.objects.endTransaction();
     }
 
     /**