Delete old duckdb index files

default/challenge_test_scramble/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:e05d95e8853cab5445fb8ca8cd096cd33b053a6e2bd78e83162274644947adbb
-size 1060864

default/challenge_train_sample/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:d02b846000a9e1334eea49929e35ddd4d0f25917220a52145ad21dd6e5000ed4
-size 1060864

default/challenge_validation_sample/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:c006a0b0c5c9ea13b6ccde003fe6d20fe3fba090a48f5c93ae0f8ac134f9e4b0
-size 1060864

default/test/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:4fbdf3785193cba1deefc06f57334013a381b4c91baa5ed4c174c15bc27fb520
-size 1323008

default/train/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:fe285129846a5842f5a71bf40177dce23bc8e781056bd31335266e992f7848f6
-size 1585152

default/validation/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:74ee7ae6a6a24c35b27acd4d6bbf14b2136cd80441fe77fdbac3124cf03a0d2f
-size 1060864