Update duckdb index files

.gitattributes

@@ -58,3 +58,4 @@ d0rj--wikisum/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 d0rj--wikisum/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:ef831944dc41dafc838f037579dc3160acddf65895978922b310cd97e351c43e
+size 339488768