fix test cov

Author: chelsea-lin

db_dtypes/json.py

@@ -80,7 +80,7 @@ def __init__(self, values) -> None:
         elif isinstance(values, pa.ChunkedArray):
             pa_data = values
         else:
-            raise ValueError(f"Unsupported type '{type(values)}' for JSONArray")
+            raise NotImplementedError(f"Unsupported type '{type(values)}' for JSONArray")
 
         # Ensures compatibility with pandas version 1.5.3
         if hasattr(self, '_data'):