Delete old duckdb index files

default/exercise_contest_test/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:4cdd66be9fc0d8a89d35f0c7db15041a1706f84751210009c8a2ff4d61ebb323
-size 68956160

default/exercise_contest_train/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:607244ff88dc43892a07f500d09949b5cfb9a0df6992a8e8787b47d8895b520d
-size 347090944

default/exercise_contest_valid/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:64d321e3a357eecbde9ea43b7c304abcd23eda4cf3b952c484c7b9a2a299ae3b
-size 36974592

default/final_test/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:462ad9e34e3bb1e15ab7ed048dbd65624c8fb855b848f404bd1f733071767848
-size 74985472

default/first_stage_test/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:e1e74f7598983a0d7037ebd655c0f6e0c190e60018ce1e1f9c22af02a2a39e91
-size 393752576

default/first_stage_train/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:c2663a212f7629cc7323150e9e1cc3c171b2292720e766600026fc5729f145c3
-size 2916102144