FIX: TRUE and FALSE can also be functions

Previously the engine was internally transforming TRUE() to TRUE

Note that the friendly giant implements this only for
compatibility reasons

base/src/test/mod.rs

@@ -41,6 +41,7 @@ mod test_sheet_markup;
 mod test_sheets;
 mod test_styles;
 mod test_trigonometric;
+mod test_true_false;
 mod test_workbook;
 mod test_worksheet;
 pub(crate) mod util;