Updated validation file name

data_preparation.py

@@ -106,7 +106,7 @@ if __name__ == "__main__":
     
     # add gem id and save valid.json
     validation = add_gem_id(validation, "validation")
-    with open("valid.json", "w") as val_file:
+    with open("validation.json", "w") as val_file:
         json.dump(validation, val_file, indent = 2)
         val_file.close()