Update duckdb index files

.gitattributes

@@ -347,3 +347,4 @@ el_other/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 el_other/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 el_wikipedia/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 en_caselaw/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
+en_contracts/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

en_contracts/validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:1db111677ffdb0f7a631ab6bec59c8b47a3d6c19fc15d3bd91b3dd7db226445b
+size 20197376