Fix: Avoid error from null value for observer in timeoutStartSubscriptionAck function

[KvNGCzA]

Issue #, if available:
#515 #544 #596

Description of changes:
An if statement to make sure that the observer exists before it tries to call the properties of observer in timeoutStartSubscriptionAck function

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[99darwin]

Please pull this in!

[ankur014]

There have been multiple issues opened related to this, can we get this merged, please?

[loganbertrand]

Can we please merge this?

[randomslap]

Can this pull request get merged please? Subscriptions are unstable and it causes app to crash due to this issue.

[jcbdev]

This issue also exists in the timeoutDIsconnect function too!

AppSyncRealTimeSubscriptionHandshakeLink.prototype._timeoutDisconnect = function () {
        this.subscriptionObserverMap.forEach(function (_a) {
            var observer = _a.observer;
            observer.error({
                errors: [__assign({}, new graphql_1.GraphQLError("Timeout disconnect"))]
            });
            observer.complete();
        });
        this.subscriptionObserverMap = new Map();
        if (this.awsRealTimeSocket) {
            this.awsRealTimeSocket.close();
        }
        this.socketStatus = types_1.SOCKET_STATUS.CLOSED;
    };

Would be good if we could cover both issues?

[ankur014]

There hasn't been any traction on this for some time, so, we tried this workaround and it seems to be working. Adding it here so that others can give it a shot as well - https://dev.to/willsamu/how-to-get-aws-appsync-running-with-offline-support-and-react-hooks-678

[KvNGCzA]

Hey @jcbdev . I opened this to fix the issue in the timeoutDisconnect function. Thanks for the suggestion.

@sammartinez @elorzafe Hey guys. This PR has been open for a while, can we please get it merged?

[99darwin]

@elorzafe are you still monitoring this? the best Holiday gift you could give us all would be merging this PR! 🎄🎅

[aehmt]

@elorzafe are you still monitoring this? the best Holiday gift you could give us all would be merging this PR! 🎄🎅

What's the hold up with this? Can someone from AWS explain?

[KvNGCzA]

@sammartinez Hi, have I missed a step in opening this PR? I read and followed the contributing guidelines. Maybe I missed something. Kindly give feedback on the next steps.

[elorzafe]

@KvNGCzA thanks for this PR.

I am sorry for the delay. We will do a release of this ASAP

[KvNGCzA]

@elorzafe Thank you for your response. Cheers.