1.8.2 merge into master - the version of open mct after the last but equally as important (#4611)

* Release 1.8.2

* Trasactions tests are ids equal fix 1.8.2 (#4593)

* test fix

* return promise on 'onSave'

* "Export as JSON" yielding corrupted data #4577 (#4585)

https://github.com/nasa/openmct/issues/4577

* Fix date picker default time setting (#4581)

Fix mode dropdown position
Fix unlistening of upstream events

* Bar graph composition policy fix to allow condition set creation. (#4598)

* Use image timestamp instead of image index to show large view (#4591)

* Use image timestamp instead of image index to show large view

* Fix failing test

Co-authored-by: Nikhil <nikhil.k.mandlik@nasa.gov>

src/plugins/exportAsJSONAction/ExportAsJSONAction.js

@@ -60,6 +60,7 @@ export default class ExportAsJSONAction {
      * @param {object} objectpath
      */
     invoke(objectpath) {
+        this.tree = {};
         const root = objectpath[0];
         this.root = JSON.parse(JSON.stringify(root));
         const rootId = this._getId(this.root);