From the datasheet it is highly suggestive that you to connect both pads for each terminal:
Furthermore, from that datasheet we have the following two statements:
By incorporating a dual-contact design we were able to maximize current rating (6 Amps) and minimize PCB space. ...
...
The dual-contact design also provides two solder points
for each wire eliminating the need for external anchor tabs.
I read that as implying that the reason for providing both contacts is to increase the current handling capabilities. By only using a single contact you would most likely have to de-rate the power handling capabilities accordingly.
Having both connections is also provides additional mechanical strength to the connector.
Unless there is a very good reason not to, personally I would be sure to connect both contacts to the net.