Fix type conversion warning

Change-Id: I28ecd736c14a2cbd85bf63fd032691edf44bae64

src/main/java/com/googlesource/gerrit/plugins/hooks/rtc/network/CachableResourcesFactory.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/rtc/network/CachableResourcesFactory.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/rtc/network/CachableResourcesFactory.java
index 4aba41d..3d0a5c5 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/rtc/network/CachableResourcesFactory.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/rtc/network/CachableResourcesFactory.java
@@ -33,11 +33,10 @@
     return (T) getFactory(clazz).get(url);
   }
 
-  @SuppressWarnings("unchecked")
   private <T> InternalFactory<?> getFactory(Class<T> clazz) {
     InternalFactory<?> factory = factories.get(clazz);
     if (factory == null) {
-      factory = new InternalFactory(transport, clazz);
+      factory = new InternalFactory<>(transport, clazz);
       factories.put(clazz, factory);
     }
     return factory;