[BugFix] Handle ValidationError Better

[deeleeramone]

1. Why?:

   • Some ValidationErrors were raising as Unexpected in the Python Interface.

2. What?:

   • Remove the secondary condition in the instance check for ValidationError

   • Remove redundant str wrapper inside f-string.

3. Impact:

   • More consistent ValidationError,

4. Testing Done:

Making a validation error by changing the content of a string field to a list without changing the model.

Before:

After:

Query:

Data: