Fix testhelper.deepDiffEqual (#374)

* Fix deepdiff comparison with maps

* Fix RemainingKeys function

* Fix unit tests

* Another fix of RemainingKeys

* RemainingKeys cleanup

* Simplifying RemainingKeys

* Revert continue on invalid. Fix broken tests

Related-PROD: PROD-28126

Change-Id: Ifc5afaf1278c7cff3a89b23a1fd1876aac1dff34
8 files changed