Update duckdb index files

.gitattributes

@@ -106,3 +106,4 @@ default/sst2_perturbed_typos_0.1/index.duckdb filter=lfs diff=lfs merge=lfs -tex
 default/sst2_perturbed_swapnum/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/sst2_perturbed_verbtense/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/sst2_perturbed_twitter/index.duckdb filter=lfs diff=lfs merge=lfs -text
+default/sst2_perturbed_wordcase/index.duckdb filter=lfs diff=lfs merge=lfs -text

default/sst2_perturbed_wordcase/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:fc23948b06cfc965a09fad27fd5d87c9276a730241348a6f7bfbd68d683433d1
+size 1323008