Make sure that nginx becomes PID 1

[refs #49b2f3dafcad]

Author: jfahrer

load_balancer/start.sh

@@ -1,4 +1,4 @@
 #!/usr/bin/env bash
 
 envsubst '$PROXY_PROTOCOL,$PROXY_UPSTREAM' < /etc/nginx/sites-available/default.template > /etc/nginx/sites-available/default
-nginx -g 'daemon off;'
+exec nginx -g 'daemon off;'