replace electrum/ecc with electrum_ecc package

electrum/lnonion.py

@@ -28,7 +28,8 @@ import hashlib
 from typing import Sequence, List, Tuple, NamedTuple, TYPE_CHECKING, Dict, Any, Optional, Union
 from enum import IntEnum
 
-from . import ecc
+import electrum_ecc as ecc
+
 from .crypto import sha256, hmac_oneshot, chacha20_encrypt
 from .util import profiler, xor_bytes, bfh
 from .lnutil import (get_ecdh, PaymentFailure, NUM_MAX_HOPS_IN_PAYMENT_PATH,