`NewOrderTimeInForceEnum` should support `GTE_GTC` for TP/SL orders

[zionhann]

Currently, the NewOrderTimeInForceEnum does not include the GTE_GTC option, which is required for take-profit (TP) and stop-loss (SL) orders on USDs Futures (and likely on other clients as well).

The GTE_GTC option ensures that TP/SL orders are automatically cancelled when the related position is closed. This behaviour prevents any remaining TP/SL orders from staying active after the position has been exited.

class NewOrderTimeInForceEnum(Enum):
    GTC = "GTC"
    IOC = "IOC"
    FOK = "FOK"
    GTX = "GTX"
    GTD = "GTD"
+  GTE_GTC = "GTE_GTC"