Close log file when iterator over it is exhausted

sohstationviewer/model/reftek_data/reftek_reader/log_file_reader.py

@@ -111,6 +111,7 @@ class LogFile:
     def __next__(self) -> List[str]:
         line = self.file.readline()
         if line == '':
+            self.file.close()
             raise StopIteration
         while line == '\n':
             line = self.file.readline()