Delete old duckdb index files

default/test/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:a34013e19332ea4bb270faed60c4a0eaa5514a38245d7560285e3717a5113847
-size 1847296

default/train/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:ce4e64976704f24893017f9a5f8034313f6bc6189fab3a1e5d79236bdff8a71b
-size 28585984

default/validation/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:db9d68cbf60ce90d026584f4c31a08c429135c89d35013c578d12ec4e8f2de46
-size 7352320

qbao775--PARARULE-Plus-Depth-3/train/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:f54013c8d0b9856615de6e730388e329878919ad99f00be7a8d17543e031524c
-size 28323840