Add .add_gts_column_to_cards_wide_summary()

[ddsjoberg]

The 'gts_column' is defined in the bridge function, whereas the other tbl_*() functions define the gts_column before the bridge functions. To be consistent with the other functions, we should migrate this definition to a function called .add_gts_column_to_cards_wide_summary().

This is a low priority.