Update duckdb index files

.gitattributes

@@ -6,3 +6,4 @@ copa/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 copa/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 copa/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
 hellaswag/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
+hellaswag/train/index.duckdb filter=lfs diff=lfs merge=lfs -text

hellaswag/train/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:c7930329d3fa5e565f9f4b90b08a48bbf8071b7d80951e359621e36fd62130e5
+size 1847296