deleteUnsupportedTimezoneNames(oCurrentTimezones) {
		const oDeprecatedTimezones = new Set();

		this._deleteUnsupportedTimezoneNames(oCurrentTimezones, oDeprecatedTimezones);

		if (!this.#bDeprecatedTimezonesLogged && oDeprecatedTimezones.size > 0) {
			console.log("INFO: Deleted deprecated timezone translations: "
				+ Array.from(oDeprecatedTimezones).join(", "));
		}
		this.#bDeprecatedTimezonesLogged = true;
	}
Deletes unsupported time zone IDs from the given time zone names object recursively.
Every deleted time zone ID is added to the deprecated time zones set and logged once after completion.

@param {Object<string, any>} oCurrentTimezones The given time zone names reference object