Fix sql script name conflict (#411)

* Fix sql script name conflict

There are two V11__ files due to concurrent merge. Renamed one
to V12__

Also removed a @NotNull annotation, which is the fist in the code base.
Most of the code base use @Nullable instead. If we do want to use
@NotNull, we may want to use the javax one instead.

core/src/main/java/google/registry/schema/tld/PremiumListCache.java

@@ -28,7 +28,6 @@ import com.google.common.cache.LoadingCache;
 import google.registry.util.NonFinalForTesting;
 import java.math.BigDecimal;
 import java.util.Optional;
-import org.jetbrains.annotations.NotNull;
 import org.joda.time.Duration;
 
 /** Caching utils for {@link PremiumList}s. */
@@ -52,7 +51,7 @@ class PremiumListCache {
         .build(
             new CacheLoader<String, Optional<PremiumList>>() {
               @Override
-              public Optional<PremiumList> load(@NotNull String premiumListName) {
+              public Optional<PremiumList> load(String premiumListName) {
                 return PremiumListDao.getLatestRevision(premiumListName);
               }
             });