Jandex warning at boot time about JsonString

[pilhuhn]

Describe the bug

At system start, the following warning is printed:

2020-07-15 11:54:34,465 WARN  [io.qua.dep.ste.ReflectiveHierarchyStep] (build-32) Unable to properly register the hierarchy of the following classes for reflection as they are not in the Jandex index:
        - javax.json.JsonString (source: com.redhat.cloud.policies.app.rest.PolicyCrudService[javax.ws.rs.core.Response validateName(@NotNull javax.json.JsonString policyName, java.util.UUID id)])
Consider adding them to the index either by creating a Jandex index for your dependency via the Maven plugin, an empty META-INF/beans.xml or quarkus.index-dependency properties.");.

Code looks like

  @POST
  @Path("/validate-name")
  public Response validateName(@NotNull JsonString policyName, @QueryParam("id") UUID id) {

JsonString is pulled into Quarkus via

• io.quarkus:quarkus-resteasy-jsonb:1.6.0.Final
  ** org.jboss.resteasy:resteasy-json-binding-provider:4.5.5.Final
  *** org.glassfish:jakarta.json:1.1.6

so I would expect that this is already registered in Quarkus by default.
This warning was not printed before 1.6

Expected behavior

Print no warning, as it is already registered

[mkouba]

It seems that we produce the fiReflectiveHierarchyBuildItem twice. One backed by the CombinedIndexBuildItem and the other one backed by the BeanArchiveIndexBuildItem. And the one backed by CombinedIndexBuildItem results in the warning. I'll send a PR to fix this particular issue but the overall "reflection registration strategy" would probably deserve some refactoring...