[tests] Remove deprecated addwitnessaddress call from wallet_dump.py
[tests] Remove deprecated addwitnessaddress call from wallet_dump.py

addwitnessaddress is deprecated. Remove the call to that RPC from
wallet_dump.py and improve testing of all types of address (legacy,
p2sh-segwit and bech32)

chaincoin/chaincoin,chaincoin/chaincoin,chaincoin/chaincoin,chaincoin/chaincoin,chaincoin/chaincoin,chaincoin/chaincoin