Update duckdb index files

.gitattributes

@@ -90,3 +90,4 @@ iwslt2017-en-zh/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-it-en/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-fr-en/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 iwslt2017-it-en/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
+iwslt2017-en-ko/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

iwslt2017-en-ko/validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:8e035514f291ac9d72ba6111df0f0e9940d14687b94ba364ff3697133934adfe
+size 1060864