Update duckdb index files

.gitattributes

@@ -333,3 +333,4 @@ cs_contracts/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 da_wikipedia/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 da_other/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 de_caselaw/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
+de_contracts/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text

de_contracts/validation/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:5664d503830ff81dc2742e18360ccbe600891d8287ce16df3ef8a57ad3847639
+size 28323840