Update duckdb index files

.gitattributes

@@ -57,3 +57,4 @@ jxu124--refcocog/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 jxu124--refcocog/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/test/index.duckdb 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 sha256:859b7693ffbf7afca2492a8d6861f83a47f38ca945b693ee41539021df9f0ce1
+size 6041600