[FIX] Leave room request not removing the subscription from the app

[cking-vonix]

Proposed changes

When a subscription is removed from the server via another client, when the
mobile app is relaunched the subscriptions were not being removed properly.
Changed the logic to use the subscriptionResult.remove array from the server
and the _id property to fix.

Issue(s)

#3756

How to test or reproduce

Steps to reproduce same as in issue:

• Open mobile application and login to initialize database
• Close the app completely
• Login via web to same account and leave (not delete) a room to remove the subscription for that user.
• Re-open mobile application and the room that was left still exists

Screenshots

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• Improvement (non-breaking change which improves a current function)
• New feature (non-breaking change which adds functionality)
• Documentation update (if none of the other choices apply)

Checklist

• I have read the CONTRIBUTING doc
• I have signed the CLA
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works (if applicable)
• I have added necessary documentation (if applicable)
• Any dependent changes have been merged and published in downstream modules

Further comments

[diegolmello]

Nice fix! We're going to QA it soon. Thanks!

[diegolmello]

We can't update your branch, because it's from an org.
We merged at #3768 though.
Thanks for your contribution!