addUnitMappings(mUnitMappings) {
			// add custom units, or remove the existing ones if none are given
			const mExistingUnits = Formatting.getUnitMappings();
			if (mExistingUnits){
				mUnitMappings = extend({}, mExistingUnits, mUnitMappings);
			}
			Formatting.setUnitMappings(mUnitMappings);
		}
Adds unit mappings.
Similar to {@link .setUnitMappings} but instead of setting the unit mappings, it will add additional ones.
@param {object} mUnitMappings unit mappings
@see {@link module:sap/base/i18n/Formatting.setUnitMappings}
@private
@since 1.116.0