[deb/rpm] On upgrade, restart kibana service

This adds a new environment variable KBN_RESTART_ON_UPGRADE with a
default value of true.  In an upgrade scenario Kibana will automatically
restart.

Closes elastic#9863

src/dev/build/tasks/os_packages/package_scripts/post_install.sh

@@ -1,6 +1,11 @@
 #!/bin/sh
 set -e
 
+# source the default env file
+if [ -f "-<%= envFile %>" ]; then
+    . "envFile}"
+fi
+
 export KBN_PATH_CONF=${KBN_PATH_CONF:-<%= configDir %>}
 
 set_chmod() {
@@ -71,4 +76,12 @@ if [ "$IS_UPGRADE" = "true" ]; then
   if command -v systemctl >/dev/null; then
       systemctl daemon-reload
   fi
+
+  if ["$KBN_RESTART_ON_UPGRADE" = "true"]; then
+    echo -n "Restarting kibana service..."
+    if command -v systemctl >/dev/null; then
+        systemctl restart kibana.service || true
+    fi
+    echo " OK"
+  fi
 fi

src/dev/build/tasks/os_packages/service_templates/systemd/etc/default/kibana

@@ -1,13 +1,5 @@
 user="kibana"
 group="kibana"
-chroot="/"
-chdir="/"
-nice=""
-
-
-# If this is set to 1, then when `stop` is called, if the process has
-# not exited within a reasonable time, SIGKILL will be sent next.
-# The default behavior is to simply log a message "program stop failed; still running"
-KILL_ON_STOP_TIMEOUT=0
 
 KBN_PATH_CONF="/etc/kibana"
+KBN_RESTART_ON_UPGRADE="true"