Update duckdb index files

.gitattributes

@@ -84,3 +84,4 @@ temporal/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 transitive/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 transitive/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 verbcorner/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
+verbcorner/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

verbcorner/validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:37359d260baefe459c69ef6c09e634badc36a51c6920991d6124c6a11ed09de9
+size 1585152