Fix AnsibleUnsafeText when copying files larger than SMALL_FILE_LIMIT

Small files are carried in-band in the communication between
controller and remote, with larger files being copied by falling back
to a more traditional ansible put_file mechanism. This large
file code path was missed in b822f20.

ansible_mitogen/connection.py

@@ -1129,6 +1129,6 @@ class Connection(ansible.plugins.connection.ConnectionBase):
         self.get_chain().call(
             ansible_mitogen.target.transfer_file,
             context=self.binding.get_child_service_context(),
-            in_path=in_path,
+            in_path=ansible_mitogen.utils.unsafe.cast(in_path),
-            out_path=out_path
+            out_path=ansible_mitogen.utils.unsafe.cast(out_path)
         )