No auth while waiting for build to finish

When waiting for a group build to finish in `PncBuilder`, get a new
anonymous GroupBuildClient to know the state of the group build.

If we use the regular groupBuildClient, its access token might have
already expired and we'll get a 401 error eventually.

pig/src/main/java/org/jboss/pnc/bacon/pig/impl/pnc/PncBuilder.java

@@ -163,7 +163,8 @@ boolean isSuccessfullyFinished(String groupBuildId) {
         // log set to info for CPaaS to detect infinite loop
         log.info("Checking if group build {} is successfully finished", groupBuildId);
         try {
-            GroupBuild groupBuild = groupBuildClient.getSpecific(groupBuildId);
+            GroupBuildClient anonymousGroupBuildClient = new GroupBuildClient(getPncConfiguration(false));
+            GroupBuild groupBuild = anonymousGroupBuildClient.getSpecific(groupBuildId);
             switch (groupBuild.getStatus()) {
                 case BUILDING:
                     return false;