Remove old 6MT-3digit split

6MT-3digit/test-00000-of-00001.parquet

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:bec9b70075658e87b5c06cf8d41ee660bcd88fd492ebc9dd47e64c096aa62966
-size 1222680

6MT-3digit/train-00000-of-00001.parquet

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:71204e261eeac5afe7336cda77c78e42ec7914d29a04db735c88260f1f1d66e3
-size 10131045