[python-sdk] fix client.py offer_token and claim_token
[python-sdk] fix client.py offer_token and claim_token

aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core