journalist: do not hardcode 60 seconds
journalist: do not hardcode 60 seconds

In the flash message using Journalist._LOGIN_ATTEMPT_PERIOD instead

conorsch/securedrop,micahflee/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,micahflee/securedrop,heartsucker/securedrop,ehartsuyker/securedrop,micahflee/securedrop,heartsucker/securedrop,heartsucker/securedrop,conorsch/securedrop,conorsch/securedrop,heartsucker/securedrop,conorsch/securedrop,garrettr/securedrop,micahflee/securedrop,garrettr/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,conorsch/securedrop,heartsucker/securedrop,ehartsuyker/securedrop,garrettr/securedrop,garrettr/securedrop