Caps LED ON but caps lock is disabled after logout

[Summary]
The Caps LED is on but the caps lock is disable (typing in lowercase) in gdm login screen after user login/out twice.

[Steps to reproduce]
1. Install Ubuntu 20.04.3
2. Login and press "Caps lock" button
3. Make sure the typing output is in uppercase
4. Logout, back to gdm login screen
5. Input the password which is in lowercase but the "Caps LED" keeps ON

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When user login to gnome, the caps lock will be turned off even if the caps lock is ON in gdm.
It looks to me that when initialing a gnome session, it will call `state-changed` to make the Caps lock turns off.
If so, then we could make sure the logout action calls `state-changed` as well.

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$ dpkg -l | grep 'gdm\|gnome-shell\|gdk'
ii gdm3 3.36.3-0ubuntu0.20.04.4 amd64 GNOME Display Manager
ii gir1.2-gdkpixbuf-2.0:amd64 2.40.0+dfsg-3ubuntu0.2 amd64 GDK Pixbuf library - GObject-Introspection
ii gir1.2-gdm-1.0:amd64 3.36.3-0ubuntu0.20.04.4 amd64 GObject introspection data for the GNOME Display Manager
ii gnome-shell 3.36.9-0ubuntu0.20.04.2 amd64 graphical shell for the GNOME desktop
ii gnome-shell-common 3.36.9-0ubuntu0.20.04.2 all common files for the GNOME graphical shell
ii gnome-shell-extension-appindicator 33.1-0ubuntu0.20.04.2 all AppIndicator/KStatusNotifierItem support for GNOME Shell
ii gnome-shell-extension-desktop-icons 20.04.0-3~ubuntu20.04.3 all desktop icon support for GNOME Shell
ii gnome-shell-extension-ubuntu-dock 68ubuntu1~20.04.1 all Ubuntu Dock for GNOME Shell
ii libgdk-pixbuf2.0-0:amd64 2.40.0+dfsg-3ubuntu0.2 amd64 GDK Pixbuf library
ii libgdk-pixbuf2.0-bin 2.40.0+dfsg-3ubuntu0.2 amd64 GDK Pixbuf library (thumbnailer)
ii libgdk-pixbuf2.0-common 2.40.0+dfsg-3ubuntu0.2 all GDK Pixbuf library - data files
ii libgdm1 3.36.3-0ubuntu0.20.04.4 amd64 GNOME Display Manager (shared library)
ii yaru-theme-gnome-shell 20.04.11.1 all Yaru GNOME Shell desktop theme from the Ubuntu Community