BUG/MINOR: s6: React to SIGUSR1 when pod is getting deleted

Author: dkorunic

fs/etc/services.d/ingress-controller/run

@@ -1,5 +1,13 @@
 #!/usr/bin/with-contenv sh
 
+if [ ! -f /var/run/s6/services/.s6-svscan/SIGUSR1 ]; then
+    cat > /var/run/s6/services/.s6-svscan/SIGUSR1 <<EOF
+#!/bin/sh
+kill -SIGTERM 1
+EOF
+    chmod +x /var/run/s6/services/.s6-svscan/SIGUSR1
+fi
+
 MEMLIMIT=$(free -m | awk '/Mem:/ {print int($2 / 3)}')
 
 CG_LIMIT_FILE="/sys/fs/cgroup/memory/memory.limit_in_bytes"