Stable dc voltage for raspberry pi connected with Truck power outlet
It seems you got the basic connection right: You switch the 3.3V supply to the GPIO pins, and you have the internal pull-down resistor enabled, so the pin is pulled low unless something actively supplies current into the pin (in your case, the switch).

The internal pull-down resistor of the Raspberry Pi is 50kOhm, so you do not need a lot of current to make the input high. It is quite likely that you can get enough current through interference to create a false rising edge, especially if there are some inches of wire between the Pi and the button, and especially if you are in an electrically noise environment. My first attempt would be to provide an external pull-down resistor (as shown in the diagram you provided) of 1kOhm to 2kOhm instead of (just) the internal pull-down resistor of 50 kOhm (lower numbers are stronger). The diagram shows 10k resistors, which are OK in a controlled environment, but in a truck a lower pull-down value is recommended for better interference suppression.