Update duckdb index files

.gitattributes

@@ -459,3 +459,4 @@ default/lt.test/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/lv.test/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/lv.validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/mdf.test/index.duckdb filter=lfs diff=lfs merge=lfs -text
+default/mdf.validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

default/mdf.validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:13c6c50db967773bf69220cbfc8a1b6b05c04628519ee0d883522b611c75f6a2
+size 1060864