fix: add amount to TokenMintTransaction in deduplication tests

Signed-off-by: Mohit Yadav <ymohit799057@gmail.com>

Author: mohityadav8

tests/unit/signature_deduplication_test.py

@@ -1,5 +1,3 @@
-# RENAME FILE TO: tests/unit/signature_deduplication_test.py
-
 from __future__ import annotations
 
 from hiero_sdk_python.account.account_id import AccountId
@@ -14,6 +12,7 @@ def test_duplicate_signature_not_added():
     tx.set_transaction_id(TransactionId.generate(AccountId(0, 0, 1234)))
     tx.set_node_account_id(AccountId(0, 0, 3))
     tx.set_token_id(TokenId(0, 0, 1))
+    tx.set_amount(100)
     key = PrivateKey.generate_ed25519()
     tx.freeze()
     tx.sign(key)
@@ -28,6 +27,7 @@ def test_multiple_keys_still_work():
     tx.set_transaction_id(TransactionId.generate(AccountId(0, 0, 1234)))
     tx.set_node_account_id(AccountId(0, 0, 3))
     tx.set_token_id(TokenId(0, 0, 1))
+    tx.set_amount(100)
     key1 = PrivateKey.generate_ed25519()
     key2 = PrivateKey.generate_ed25519()
     tx.freeze()
@@ -38,7 +38,7 @@ def test_multiple_keys_still_work():
     assert len(sig_pairs) == 2, "Expected 2 signatures for different keys"
     pubkey_prefixes = {sp.pubKeyPrefix for sp in sig_pairs}
     expected_prefixes = {
-        key1.public_key().to_bytes(),
-        key2.public_key().to_bytes(),
+        key1.public_key().to_bytes_raw(),
+        key2.public_key().to_bytes_raw(),
     }
     assert pubkey_prefixes == expected_prefixes, "Signatures should match key1 and key2 exactly"