Tenting, and want to hookup my laptop to RV power hookup

I'd advise against plugging in a 30 to 15 amp converter and using it directly.
If something short circuits in your 15 amp cabling it might not be enough to trip the 30 amp breaker (if there even is one) on the electricity pole.
As noted in the description it's made for RV's and in my experience those always have a breaker panel inside to provide the required protection.

Here in Europe we use the blue 220v 16A connectors at most camp sites.
I use a 10m extension cord with integrated MCCB (protects agains over current) and RCD (protects agains electric shocks) circuit breakers.

Besides being fairly waterproof and outdoor rated it also has sturdy attachment points so you can keep it off the ground in case of rain/flooding.

I was unable to find an American equivalent of this product but did come across a few in line protectors for camping.

Example picture below:

Notice that the ad says:

For use when RV has 15 AMP power and needs to plug into 30 AMP power source

Now notice the 15 Amp receptacle side of the adaptor:

This is a standard household outlet, which I suspect matches your charger's plug.

I.e. if you rent the 15A hookup, you shouldn't need an adaptor. (But it's good to confirm this when making the reservation.)