Tests: Adds expects for observables (#28929)

* Tests: Adds expects for observables

* Refactor: renames matcher

* Chore: changed jest version and removed as dev dependency

* Refactor: Changes after PR review

* wip

* Chore: revert

* Chore: Adds jest-matcher-utils

* Chore: fixed merge error

* Tests: Removed inline snapshots as they are env dependent

* Tests: missed a snapshot

* Refactor: Removed type file after PR comments

package.json

@@ -163,6 +163,7 @@
     "jest": "26.4.2",
     "jest-canvas-mock": "2.2.0",
     "jest-date-mock": "1.0.8",
+    "jest-matcher-utils": "26.0.0",
     "lerna": "^3.20.2",
     "lint-staged": "10.0.7",
     "load-grunt-tasks": "5.1.0",