Adapt to latest AcceptCreate<> interface on master

Change-Id: I884227f8fa8404194afeb6aff04a93e33452e503
diff --git a/src/main/java/com/googlesource/gerrit/plugins/manager/AvailablePluginsCollection.java b/src/main/java/com/googlesource/gerrit/plugins/manager/AvailablePluginsCollection.java
index 880384f..a0e595a 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/manager/AvailablePluginsCollection.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/manager/AvailablePluginsCollection.java
@@ -59,7 +59,7 @@
   }
 
   @Override
-  public <I> RestModifyView<TopLevelResource, I> create(TopLevelResource parent, IdString id)
+  public RestModifyView<TopLevelResource, ?> create(TopLevelResource parent, IdString id)
       throws RestApiException {
     throw new IllegalArgumentException("Operation not supported");
   }