fix: manage receiver in proper lifecycle callbacks
fix: manage receiver in proper lifecycle callbacks

This fix is twofold:

1) Unregisters the receiver which was not being done at all
2) Moves the register/unregister calls to the onStart and onStop
lifecycle callbacks as per Android best practices

References https://outsystemsrd.atlassian.net/browse/RNMT-3515

OutSystems/Cordova-OutSystems-AppFeedback,OutSystems/Cordova-OutSystems-AppFeedback