Update duckdb index files

.gitattributes

@@ -76,3 +76,4 @@ train.clean.360/partial-train.clean.360/index.duckdb filter=lfs diff=lfs merge=l
 train.other.500/partial-train.other.500/index.duckdb filter=lfs diff=lfs merge=lfs -text
 test.clean/test.clean/index.duckdb filter=lfs diff=lfs merge=lfs -text
 train.10/train.10/index.duckdb filter=lfs diff=lfs merge=lfs -text
+validation.clean/validation.clean/index.duckdb filter=lfs diff=lfs merge=lfs -text

validation.clean/validation.clean/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:98090e0f08c0499f6da18a260bd9bf511f0ce48167b0fb2737399211d887fa7f
+size 339750912