Filter out NA sources from citation summary table source list

[TNRiley]

The citation summary table provides precision/sensitivity calculations for anything labeled search with a second subset for anything with a designated label (often benchmark, screened, final). It will currently show the selected label as NA in the rows, this should be removed.

in the example below you can see that the 36 items that were included (labeled as final) appear in the second half of the table with NA as their source.

I believe we'll just want to hide/filter this row as we need the data associated with the final label to calculate the information on this table.