Update cheatsheets

tldr/linux/systemctl-exit

@@ -0,0 +1,21 @@
+---
+syntax: markdown
+tags: [tldr, linux]
+source: https://github.com/tldr-pages/tldr.git
+---
+# systemctl exit
+
+> Ask the service manager to quit.
+> More information: <https://www.freedesktop.org/software/systemd/man/systemctl.html#exit%20EXIT_CODE>.
+
+- Exit the user service manager:
+
+`systemctl --user exit`
+
+- Exit the user service manager with a specific exit code:
+
+`systemctl --user exit {{code}}`
+
+- Ask the container’s service manager to exit (equivalent of `systemctl poweroff` if not in a container):
+
+`systemctl exit`