Update imports for SellType in tests

tests/edge/test_edge.py

@@ -12,8 +12,8 @@ from pandas import DataFrame, to_datetime
 
 from freqtrade.data.converter import ohlcv_to_dataframe
 from freqtrade.edge import Edge, PairInfo
+from freqtrade.enums import SellType
 from freqtrade.exceptions import OperationalException
-from freqtrade.strategy.interface import SellType
 from tests.conftest import get_patched_freqtradebot, log_has
 from tests.optimize import (BTContainer, BTrade, _build_backtest_dataframe,
                             _get_frame_time_from_offset)