Function is_release_version_string 

pub fn is_release_version_string(value: &str) -> bool

Whether value is a release version this schema may carry.

^\d+\.\d+\.\d+(-[0-9A-Za-z.]+)?$ — the rule already written on Batch::app_version, applied to previous_version as well because that field is read back from state.json rather than built in this process.