Fix a few Java 9+isms and ignore IML files (#973)

This allows us to run tests in IDEA which is significantly quicker. We
shouldn't be using anything past Java 8 anyway since that's what GAE
runs with.

core/src/main/java/google/registry/backup/ReplayCommitLogsToSqlAction.java

@@ -140,11 +140,13 @@ public class ReplayCommitLogsToSqlAction implements Runnable {
     transaction.stream()
         .sorted(ReplayCommitLogsToSqlAction::compareByWeight)
         .forEach(
-            versionedEntity ->
-                versionedEntity
-                    .getEntity()
-                    .ifPresentOrElse(
-                        this::handleEntityPut, () -> handleEntityDelete(versionedEntity)));
+            versionedEntity -> {
+              if (versionedEntity.getEntity().isPresent()) {
+                handleEntityPut(versionedEntity.getEntity().get());
+              } else {
+                handleEntityDelete(versionedEntity);
+              }
+            });
   }
 
   private void handleEntityPut(Entity entity) {

core/src/main/java/google/registry/tools/javascrap/BackfillRegistryLocksCommand.java

@@ -151,7 +151,7 @@ public class BackfillRegistryLocksCommand extends ConfirmingCommand
     return domains.stream()
         .filter(d -> d.getDeletionTime().isAfter(now))
         .filter(d -> d.getStatusValues().containsAll(REGISTRY_LOCK_STATUSES))
-        .filter(d -> RegistryLockDao.getMostRecentByRepoId(d.getRepoId()).isEmpty())
+        .filter(d -> !RegistryLockDao.getMostRecentByRepoId(d.getRepoId()).isPresent())
         .collect(toImmutableList());
   }
 }