Update duckdb index files

.gitattributes

@@ -3,3 +3,4 @@ allenai--multixscience_sparse_max/parquet-validation.parquet filter=lfs diff=lfs
 allenai--multixscience_sparse_max/parquet-test.parquet filter=lfs diff=lfs merge=lfs -text
 allenai--multixscience_sparse_max/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 allenai--multixscience_sparse_max/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
+allenai--multixscience_sparse_max/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

allenai--multixscience_sparse_max/validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:60f7e0511574c3f71096d20df60092844c613c030b29906d0ccbf220bced8c95
+size 19673088