Fix some IDE warnings, mostly around type safety on the Python side

solarconditionsproviders/giroionosonde.py

@@ -28,7 +28,8 @@ class GIROIonosonde(SolarConditionsProvider):
         self._thread = None
         self._stop_event = Event()
 
-    def _load_stations(self):
+    @staticmethod
+    def _load_stations():
         stations = []
         with open(STATIONS_INDEX, newline='') as f:
             for row in csv.reader(f):