Pull request: 4223 cmd update

Merge in DNS/adguard-home-wiki from 4223-cmd-update to master

Squashed commit of the following:

commit a129f119b64ceb2638c5bd661c505a2ede664a47
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Tue Nov 15 13:13:28 2022 +0200

    4223 cmd update

commit 938b249b21d5f200eee4a96dd5df3a9feebb901a
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Mon Nov 14 14:07:40 2022 +0200

    4223 cmd update

Configuration.md

@@ -37,6 +37,7 @@ Options:
   --pidfile VALUE                    Path to a file where PID is stored.
   --check-config                     Check configuration and exit.
   --no-check-update                  Don't check for updates.
+  --update                           Update application and exit.
   --no-mem-optimization              Deprecated.  Disable memory optimization.
   --no-etc-hosts                     Deprecated.  Do not use the OS-provided hosts.
   --local-frontend                   Use local frontend directories.

Getting-Started.md

@@ -187,6 +187,16 @@ are disabled.  Update the image instead.
 
 
 
+   ###  Command-line update
+
+To update AdGuard Home package without the need to use Web API run:
+
+```sh
+./AdGuardHome --update
+```
+
+
+
 ##  <a href="#configure-devices" id="configure-devices" name="configure-devices">Configuring Devices</a>
 
    ###  Router