static setDefaultConfig(config) {
		if (typeof config !== "object" || config === null) {
			throw new TypeError(
				"RuleTester.setDefaultConfig: config must be an object",
			);
		}
		sharedDefaultConfig = config;

		// Make sure the rules object exists since it is assumed to exist later
		sharedDefaultConfig.rules = sharedDefaultConfig.rules || {};
	}
Set the configuration to use for all future tests
@param {Object} config the configuration to use.
@throws {TypeError} If non-object config.
@returns {void}