Fixing broken method

Author: adrianoaru-nhs

classes/episode/latest_episode_latest_investigation_dataset.py

@@ -52,6 +52,6 @@ def from_description(cls, description: str) -> str:
             ValueError: If the description is not recognized.
         """
         key = description.strip().lower()
-        if key not in cls._valid_values:
+        if key not in (value.lower() for value in cls._valid_values):
             raise ValueError(f"Unknown investigation dataset filter: '{description}'")
         return key