fix: UOM whole number check truncated instead of rounding

cint truncates, so a stock_qty of 1999.9998 (dust from qty times
conversion factor) compared as abs(1999 - 2000.0) > epsilon and was
rejected as fractional even though it rounds to a whole number at
field precision, with the error confusingly printing the rounded
value: 'Quantity (2000.0) cannot be a fraction'. Round to field
precision first, then require the result to be a whole number.
Dust above an integer already passed; this fixes the asymmetry for
dust below.

erpnext/utilities/transaction_base.py

@@ -618,13 +618,13 @@ def validate_uom_is_integer(doc, uom_field, qty_fields, child_dt=None):
 			for f in qty_fields:
 				qty = d.get(f)
 				if qty:
-					precision = d.precision(f)
-					if abs(cint(qty) - flt(qty, precision)) > 0.0000001:
+					qty = flt(qty, d.precision(f))
+					if qty != cint(qty):
 						frappe.throw(
 							_(
 								"Row {1}: Quantity ({0}) cannot be a fraction. To allow this, disable '{2}' in UOM {3}."
 							).format(
-								flt(qty, precision),
+								qty,
 								d.idx,
 								frappe.bold(_("Must be Whole Number")),
 								frappe.bold(d.get(uom_field)),