Is a voltage level shifter necessary?
Since the microcontroller you are using is 5 V tolerant, you can employ anything below 5 V, thus your module is fine.

There is another catch: sometimes CMOS input stages cannot tolerate an "analog" signal, i.e. they need the input voltage to be either GND, or VDD. This is because of cross conduction. This can be a problem if your port is powered via 5 V, and the high output voltage of the GPS is 3V3, i.e. somewhere in between.

Your micro has schmitt triggers input, so this is not an issue for you too.