updatectl: add page (#17431)

Co-authored-by: Managor <42655600+Managor@users.noreply.github.com>

pages/linux/updatectl.md

@@ -0,0 +1,36 @@
+# updatectl
+
+> System update utility.
+> More information: <https://www.freedesktop.org/software/systemd/man/257/updatectl.html>.
+
+- Apply an update:
+
+`updatectl update {{target}}`
+
+- Apply update and then reboot system:
+
+`updatectl --reboot update {{target}}`
+
+- Show data about the target and its versions:
+
+`updatectl list {{target}}`
+
+- Return local data about a target without fetching from the network:
+
+`updatectl --offline list {{target}}`
+
+- Suppress data headers for returned information:
+
+`updatectl --no-legend list {{target}}`
+
+- Check to see if a target has any available updates:
+
+`updatectl check {{target}}`
+
+- Clean up old versions of a specified target:
+
+`updatectl vacuum {{target}}`
+
+- Display help:
+
+`updatectl {{[-h|--help]}}`