Update duckdb index files

.gitattributes

@@ -5,3 +5,4 @@ KGraph--FB15k-237/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 KGraph--FB15k-237/train/0000.parquet filter=lfs diff=lfs merge=lfs -text
 default/train/0000.parquet filter=lfs diff=lfs merge=lfs -text
 default/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
+default/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

default/validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:21d0b4d66b4f0570e997039807f87512d0b1013727e3167f560edfb979c4f836
+size 2633728