Add `WatchEvent` to `DelByPointer` function

[raknay]

PR to address: issue

Add WatchEvent to DelByPointer function

[soumya-codes]

@raknay thanks for your contribution.

I would highly recommend you add a test for the changes. This will help validate the changes and make the code changes more resilient to failure and also help you develop a better understanding.

[soumya-codes]

@raknay we can check-in the code for now. I will create a separate a issue to add tests for the store. cc @JyotinderSingh