[GenericRestClient] Silent failure if _blockRequestUntil returns a rejected promise

[berickson1]

Currently we will silently fail and not perform the request - we should at least log something on this type of failure. Either way, this will result in dangling promises

        const promise = this._blockRequestUntil(options);
        if (!promise) {
            return this._performApiCallInternal(apiPath, action, options);
        }

        return promise.then(() => this._performApiCallInternal(apiPath, action, options));