Update duckdb index files

.gitattributes

@@ -58,3 +58,4 @@ Yuhthe--samsum/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 Yuhthe--samsum/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
+default/train/index.duckdb filter=lfs diff=lfs merge=lfs -text

default/train/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:117d53b0830a7aeae547e3f054f32fe723eac218557857fd1515b69736cb6350
+size 15216640