Bump decimal to 3.14 (#14017)

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

stdlib/@tests/stubtest_allowlists/py314.txt

@@ -8,9 +8,6 @@ _asyncio.future_discard_from_awaited_by
 _ctypes.POINTER
 _ctypes.byref
 _ctypes.pointer
-_decimal.Decimal.from_number
-_decimal.IEEEContext
-_decimal.IEEE_CONTEXT_MAX_BITS
 _heapq.heapify_max
 _heapq.heappop_max
 _heapq.heappush_max
@@ -103,8 +100,6 @@ dataclasses.Field.__init__
 dataclasses.Field.doc
 dataclasses.field
 dataclasses.make_dataclass
-decimal.Decimal.from_number
-decimal.IEEE_CONTEXT_MAX_BITS
 dis.Instruction.make
 enum.Enum.__signature__
 enum.EnumMeta.__signature__