Revert workaround for a `SWITCH` regression in `HolidaysTable` expression

[albertospelta]

Revert the workaround for the SWITCH and remove IF once the bug is fixed.
Issue created to keep track of this TODO in the source code

DaxTemplate/src/Dax.Template/Tables/Dates/HolidaysTable.cs

Lines 117 to 119 in ac0df8b

	// Workaround for a SWITCH regression that fails on service from 2022-12-10 - revert to SWITCH and remove IF once the bug is fixed
	// SWITCH (
	// TRUE,