fix linting

lofar_station_client/common/_case_insensitive_dict.py

@@ -52,6 +52,7 @@ class ReversibleIterator:
 
 class AbstractReversibleView(abc.ABC):
     """An abstract reversible view"""
+
     def __init__(self, data: UserDict):
         self.data = data
         self.len = len(data)