Update duckdb index files

.gitattributes

@@ -52,3 +52,4 @@ saved_model/**/* filter=lfs diff=lfs merge=lfs -text
 *.jpg filter=lfs diff=lfs merge=lfs -text
 *.jpeg filter=lfs diff=lfs merge=lfs -text
 *.webp filter=lfs diff=lfs merge=lfs -text
+efederici--gutenberg-it/train/index.duckdb filter=lfs diff=lfs merge=lfs -text

efederici--gutenberg-it/train/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:71273b0b59f93cf3d9c4f2f464ea50d747180c4cb756bbf06a548f50253aaaf1
+size 486813696