ag20 basin=NaN for pga rock calc

src/main/java/gov/usgs/earthquake/nshmp/gmm/AbrahamsonGulerce_2020.java

@@ -255,7 +255,7 @@ public abstract class AbrahamsonGulerce_2020 implements GroundMotionModel {
     if (in.vs30 < coeffs.vlin) {
       pgaRock = exp(calcMean(
           coeffsPGA, slab(), basin(), adjusted(), akBiasAdjusted(),
-          0.0, in.Mw, in.rRup, in.zTor, VS30_ROCK, in.z2p5));
+          0.0, in.Mw, in.rRup, in.zTor, VS30_ROCK, Double.NaN));
     }
     double μ = calcMean(
         coeffs, slab(), basin(), adjusted(), akBiasAdjusted(),