Update duckdb index files

.gitattributes

@@ -56,3 +56,4 @@ bem/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
 bem/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 bem/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 fon/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
+fon/test/index.duckdb filter=lfs diff=lfs merge=lfs -text

fon/test/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:cc9c475f692683f45f3477ca68157fabae49bc67154013a6a04fa926acc80568
+size 1060864