fix

Author: zeitlinger

instrumentation/opentelemetry-api/opentelemetry-api-1.56/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/opentelemetryapi/v1_56/incubator/config/ApplicationDeclarativeConfigProperties156Incubator.java

@@ -92,8 +92,9 @@ public <T> List<T> getScalarList(String name, Class<T> scalarType, List<T> defau
   @Nullable
   @Override
   public DeclarativeConfigProperties getStructured(String name) {
-    return new ApplicationDeclarativeConfigProperties156Incubator(
-        instrumentationConfig.getStructured(name));
+    io.opentelemetry.api.incubator.config.DeclarativeConfigProperties config =
+        instrumentationConfig.getStructured(name);
+    return config == null ? null : new ApplicationDeclarativeConfigProperties156Incubator(config);
   }
 
   @Nullable