add missing cleanup step

doc/update/4.2-to-5.0.md

@@ -195,6 +195,12 @@ sudo rm -R tmp
 sudo -u git -H mkdir tmp
 sudo chmod -R u+rwX  tmp/
 
+# create directory for pids, make sure GitLab can write to it
+sudo -u git -H mkdir tmp/pids/
+sudo chmod -R u+rwX  tmp/pids/
+
+# if you are already running a newer version of GitLab check that installation guide for other tmp folders you need to create
+
 # reboot system
 sudo reboot