Enable automatic discovery of JSON modules in the default JsonMapper configuration. (#4233)

Author: rfc3092

libs/reactive-core/src/main/java/no/nav/testnav/libs/reactivecore/web/WebClientAutoConfiguration.java

@@ -31,6 +31,7 @@ class WebClientAutoConfiguration {
 
     private static JsonMapper createDefaultJsonMapper() {
         return JsonMapper.builder()
+                .findAndAddModules()
                 .changeDefaultPropertyInclusion(incl -> incl.withValueInclusion(JsonInclude.Include.NON_NULL))
                 .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
                 .configure(DeserializationFeature.FAIL_ON_NULL_FOR_PRIMITIVES, false)