toString() {
        const resourceTypes = [];
        if (this.service) {
            resourceTypes.push("s");
        }
        if (this.container) {
            resourceTypes.push("c");
        }
        if (this.object) {
            resourceTypes.push("o");
        }
        return resourceTypes.join("");
    }
Converts the given resource types to a string.

@see https://learn.microsoft.com/en-us/rest/api/storageservices/constructing-an-account-sas