Default destroy on stale is No

[EtienneM]

╰─$ scalingo --app test-etienne integration-link-create https://framagit.org/Titizebioutifoul/sample-go-martini
? Branch to auto-deploy (empty to disable):
? Automatically deploy review apps: Yes
? Automatically destroy review apps when the pull/merge request is closed: Yes
? Hours before automatically destroying the review apps: 0
? Automatically destroy review apps after some time without deploy/commits: No
-----> Your app 'test-etienne' is linked to the repository https://framagit.org/Titizebioutifoul/sample-go-martini.
╭─emichon@biniou ~/Documents/Scalingo/golang/src/github.com/Scalingo/cli 2.4.2‹fix/484/default_destroy_stale*›
╰─$ scalingo --app test-etienne integration-link
Application: test-etienne (5d6d0d2bb4553d00019d22b6)
Integration: GitLab self-hosted (1ce487c9-3633-48be-b674-c87f2826f74f)

Repository: Titizebioutifoul/sample-go-martini
Auto Deploy: ✘
Review Apps Deploy: ✔
        Destroy on Close: instantly
        Destroy on Stale: ✘

Fix #484

[Soulou]

LGTM