Update duckdb index files

.gitattributes

@@ -75,3 +75,4 @@ iwslt2017-en-ar/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-en-de/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-en-it/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-en-zh/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
+iwslt2017-en-nl/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

iwslt2017-en-nl/validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:7905c875945cb1558c374909ea4f839b3efecda6f4836605545735b2b419d9e9
+size 1060864