async sendRequest(request) {
        return this.pipeline.sendRequest(this._httpClient, request);
    }
Send an HTTP request that is populated using the provided OperationSpec.
@typeParam T - The typed result of the request, based on the OperationSpec.
@param operationArguments - The arguments that the HTTP request's templated values will be populated from.
@param operationSpec - The OperationSpec to use to populate the httpRequest.