Use DEFAULT_REVEAL_TIMEOUT in some tests
Use DEFAULT_REVEAL_TIMEOUT in some tests

In one of them, avoid specifying reveal_timeout open option, but expect
it to be set as the default

tomashaber/raiden,hackaugusto/raiden,tomashaber/raiden,hackaugusto/raiden,tomashaber/raiden,tomashaber/raiden,tomashaber/raiden