removed some entries where trg was a duplicate of src

dataset-Ja_En-Massive.jsonl

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:d18b3a85b9d5cc349a1e701c9fd35809c704b9d9ea3a5e6ffb72a6c37577659e
-size 2171683506
+oid sha256:f46e3f3a111680d3fa70f70f01f59278dafda9756dcfcf81926123ca0e4cc6ab
+size 2161490198