[CI] Test against new Ruby 2.5
[CI] Test against new Ruby 2.5
increments/greenmat,fukayatsu/redcarpet,increments/greenmat,vmg/redcarpet,fukayatsu/redcarpet,kaneshin/redcarpet,vmg/redcarpet,kaneshin/redcarpet,vmg/redcarpet,kaneshin/redcarpet,vmg/redcarpet,increments/greenmat,fukayatsu/redcarpet,increments/greenmat,fukayatsu/redcarpet,kaneshin/redcarpet