get_filtered_behavior_session_table has bad session_types

This SDK issue is actually a VBA issue.
https://github.com/AllenInstitute/AllenSDK/issues/1975

There are sessions in the table returned by `loading.get_filtered_behavior_session_table(release_data_only=True)` that 
1) have a bad session_type `1_gratings` rather than `TRAINING_1_gratings` 
2) differ from the `session.metadata.session_type` which has the correct value

@matchings 