Update duckdb index files

.gitattributes

@@ -83,3 +83,4 @@ iwslt2017-it-nl/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-en-nl/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-it-nl/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-fr-en/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
+iwslt2017-en-nl/train/index.duckdb filter=lfs diff=lfs merge=lfs -text

iwslt2017-en-nl/train/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:74bc5a3b7aff8bb200f10f67d29fb7d5d71b0809f08b0259fee89b70e760ade9
+size 23080960