[rikiddo] Ensure that advised Rikiddo markets have enough runway for collecting subsidy

[maltekliemann]

A quick skim of the code reveals that an advised Rikiddo market can be approved one minute before it will end. On the contrary, creating a permissionless Rikiddo market with only one minute of life will result in an error (subsidy phase will be too short). This seems inconsistent and should be fixed.