Delete old duckdb index files

default/train/partial-index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:d01547416218485bfdb373607bb203c34c2fbe4c36b8318b71673282f188ef00
-size 3542888448

default/validation/index.duckdb

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:49e1096f4e9554876605878a431b8abfba828bc0a514dc79739cdbcdef6d8d78
-size 488386560