Remove transition code for set of parameter refactoring

None of the logged warnings happened in the last week.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=204307010

java/google/registry/batch/BatchModule.java

@@ -96,6 +96,6 @@ public class BatchModule {
   @Provides
   @Parameter(PARAM_RESAVE_TIMES)
   static ImmutableSet<DateTime> provideResaveTimes(HttpServletRequest req) {
-    return extractSetOfDatetimeParameters(req, PARAM_RESAVE_TIMES, null);
+    return extractSetOfDatetimeParameters(req, PARAM_RESAVE_TIMES);
   }
 }