Remove transition code for set of parameter refactoring

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

java/google/registry/module/backend/BackendModule.java

@@ -45,8 +45,7 @@ public class BackendModule {
   @Provides
   @Parameter(RequestParameters.PARAM_TLDS)
   static ImmutableSet<String> provideTlds(HttpServletRequest req) {
-    ImmutableSet<String> tlds =
-        extractSetOfParameters(req, RequestParameters.PARAM_TLDS, RequestParameters.PARAM_TLD);
+    ImmutableSet<String> tlds = extractSetOfParameters(req, RequestParameters.PARAM_TLDS);
     assertTldsExist(tlds);
     return tlds;
   }