Welcome to the Arduino forum.
I have exactly those float switches to control the water in my irrigation system. I have a solenoid valve to control the tank filling, not a pump, but the rest is the same.
My wiring has ONE lead from both switches connected to the Arduino ground, the second wire from a switch goes to one Arduino Nano pin and the second switch wire goes to another Arduino pin. Both pins are identified as input pullup.
Has been working well for about 3 years.
Good luck,
Paul