Remove not responding testnet node from unit tests

beem/blockchain.py

beem/version.py

beemapi/version.py

beembase/version.py

beemgraphenebase/version.py

setup.py

tests/beem/test_account.py

tests/beem/test_block.py

tests/beem/test_blockchain.py

tests/beem/test_cli.py

tests/beem/test_conveyor.py

tests/beem/test_steem.py

tests/beem/test_steemconnect.py

tests/beem/test_storage.py

tests/beem/test_testnet.py