cmd: Support double signal handling

Signed-off-by: Kosy Anyanwu <kosy@kinvolk.io>

cmd/habitat-operator/main.go

@@ -112,12 +112,17 @@ func run() int {
  // Relay these signals to the `term` channel.
  signal.Notify(term, syscall.SIGINT, syscall.SIGTERM)
 
- select {
- case <-term:
+ go func() {
+  <-term
  level.Info(logger).Log("msg", "received SIGTERM, exiting gracefully...")
- case <-ctx.Done():
- level.Info(logger).Log("msg", "context channel closed, exiting")
- }
+ cancelFunc()
+
+ <-term
+ os.Exit(1)
+ }()
+
+ <-ctx.Done()
+ level.Info(logger).Log("msg", "context channel closed, exiting")
 
  return 0
 }