Update duckdb index files

.gitattributes

@@ -85,3 +85,4 @@ ar_ja/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 ar_hi/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 cs_it/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
 cs_ja/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
+cs_ja/sampled_validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

cs_ja/sampled_validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:fc58b9d8ff22dc877d5b2df3aa370242721646f38ec675b4d7b8a2d23b5ac6d7
+size 14954496