Use proper class for change data query

Use the proper ChangeQueryProcessor class instead of using
a reference to the generic definition.

Change-Id: Iff0d639b74b31f7090108f6ab467993c6dc4cfae

github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/wizard/PullRequestListController.java

diff --git a/github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/wizard/PullRequestListController.java b/github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/wizard/PullRequestListController.java
index 6d0bdcb..75abcf8 100644
--- a/github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/wizard/PullRequestListController.java
+++ b/github-plugin/src/main/java/com/googlesource/gerrit/plugins/github/wizard/PullRequestListController.java
@@ -64,7 +64,7 @@
   private final ProjectCache projectsCache;
   private final GitRepositoryManager repoMgr;
   private final Provider<ReviewDb> schema;
-  private final QueryProcessor<ChangeData> qp;
+  private final ChangeQueryProcessor qp;
   private final ChangeQueryBuilder changeQuery;
 
   @Inject