Add failures in registry listing to telemetry

[StephenWeatherford]

e.g. this:

    if (loggedIntoAzure) {
        const subs: SubscriptionModels.Subscription[] = this.getFilteredSubscriptions();

        const subPool = new AsyncPool(MAX_CONCURRENT_SUBSCRIPTON_REQUESTS);
        let subsAndRegistries: { 'subscription': SubscriptionModels.Subscription, 'registries': ContainerModels.RegistryListResult }[] = [];
        //Acquire each subscription's data simultaneously
        // tslint:disable-next-line:prefer-for-of // Grandfathered in
        for (let i = 0; i < subs.length; i++) {
            subPool.addTask(async () => {
                const client = new ContainerRegistryManagement(this.getCredentialByTenantId(subs[i].tenantId), subs[i].subscriptionId);
                let regs: ContainerModels.Registry[];
                try {
                    regs = await client.registries.list();
                    subsAndRegistries.push({
                        'subscription': subs[i],
                        'registries': regs
                    });
                } catch (error) {
                    vscode.window.showErrorMessage(error); <<<<<<<<<<

[StephenWeatherford]

Another possibility would be to add error nodes.

[estebanreyl]

Ill add these to the telemetry right now. Additionally, I quite like the errorNode idea, you mentioned an azuretreedataprovider in #360 , should we wait until that is added before we add error nodes? I can try adding them in later PR's with the current model as well.

[StephenWeatherford]

It'll be easier if we wait, but thanks anyway. I'd like to handle this in a shared aware across all our extensions if possible.