Tests hang

[jayvdb]

Running cargo test on stable results in many tests not finishing within 60 seconds, and seem to go for many minutes.

...
test network::tests::test_blockchain_causes_sndblkhd has been running for over 60 seconds
test network::tests::test_network_message_sending has been running for over 60 seconds
test network::tests::test_sndblkhd has been running for over 60 seconds
test network::tests::test_sndchain has been running for over 60 seconds
test networking::api_message::tests::test_message_serialize has been running for over 60 seconds
test networking::message_types::handshake_challenge::tests::test_challenge_serialize has been running for over 60 seconds
test networking::message_types::request_block_message::tests::test_request_block_message_serialize has been running for over 60 seconds
test networking::message_types::request_blockchain_message::tests::test_request_blockchain_message_serialize has been running for over 60 seconds
test networking::message_types::send_block_head_message::tests::test_send_block_head_message_serialize has been running for over 60 seconds
test networking::message_types::send_blockchain_message::tests::test_send_blockchain_message_serialize has been running for over 60 seconds
test slip::tests::slip_addition_and_removal_from_utxoset has been running for over 60 seconds
test staking::tests::blockchain_roll_forward_staking_table_test_with_test_manager has been running for over 60 seconds
test staking::tests::blockchain_staking_deposits_test has been running for over 60 seconds
test staking::tests::staking_create_blockchain_with_many_staking_deposits_many_staker_payouts_per_block has been running for over 60 seconds
test staking::tests::staking_create_blockchain_with_two_staking_deposits_one_staker_payout_per_block has been running for over 60 seconds
test storage::tests::write_read_block_to_file_test has been running for over 60 seconds