message: Fix env variable name
  The env variable that is used to pass the container version from the
  runtime to the container has a `NORTHSTAR_` prefix.
diff: fn main() {
  - let version = std::env::var("VERSION").unwrap_or_else(|_| "unknown".into());
  + let version = std::env::var("NORTHSTAR_VERSION").unwrap_or_else(|_| "unknown".into());
  loop {
  println!("Hello from the seccomp example version {}!", version);
  std::thread::sleep(std::time::Duration::from_secs(5));
  