Update example default detector to LUX/LZ

[seriksen]

in helpers.py the default detector is currently XENON10, we should consider updating this to a modern detector.

[albert-physics]

I don't think that the example actually makes a difference. NESTCalc (for reasons I do not understand) requires a detector even for detector agnostic things like the yields. I think the only things that use the XENON10 detector actually do not depend on the detector. I think in theory these could be replaced with VDetector to make this clearer, but I have not personally not tried it. I am also unsure if the cache logic is actually useful as creating a detector object should be very quick so I guess that could be simplified to make things easier, I guess maybe this is to speed things up for the for-loop