Update duckdb index files

.gitattributes

@@ -99,3 +99,4 @@ iwslt2017-en-zh/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-ja-en/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-nl-it/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-nl-ro/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
+iwslt2017-nl-en/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

iwslt2017-nl-en/validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:4cc05812dc02404292492e766eeb4677dfd9bc08a8125c455bde19f50a2f643a
+size 1060864