Automatically set `-y` in CI

[erri120]

CI's don't have console input, as such it would be nice to automatically select -y when running in CI. You can detect CI with the environment variable CI, which will be set to true.

If you don't manually set -y in CI, you'll get this error:

Continue? [N/y]: 
FAILED
Cannot read keys when either application does not have a console or when console input has been redirected. Try Console.Read.

[kuiperzone]

Will add in next version.

[kuiperzone]

Will be version 1.7 shortly.