static getCLDRTag(sUI5Tag) {
		return Generator.#mUI5toCLDRTag[sUI5Tag] || sUI5Tag.replace(/_/, "-");
	}
Gets the langugage tag as used in CLDR from the language tag as used in UI5.

@param {string} sUI5Tag The UI5 language tag, e.g. "en", "de_CH", "zh_CN" or "sr_Latn"
@returns {string} The corresponding CLDR language tag (e.g. "en-US", "de", "zh-Hans-CN", "sr-Latn")