Sharing: VNC password isn't changed when the remote desktop password is changed while VNC is disabled

[Jeremy Bícha]

Impact
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VNC password isn't changed when the remote desktop password is changed while VNC is disabled

The password is successfully set for VNC if VNC is enabled.

This bug is probably uncommon but could be annoying if it does happen.

Test Case
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1. Open the Settings app
2. In the left sidebar, choose Sharing.
3. Turn on sharing in the top bar of the app the click Remote Desktop
4. Turn on Remote Desktop
5. Turn on "Enable Legacy VNC Protocol"
6. Click ⋮ and switch to "Require a password"
7. Turn off "Enable Legacy VNC Protocol"
8. Change the Password at the bottom of the dialog.
9. Turn on "Enable Legacy VNC Protocol"
10. Open a terminal and run grdctl status --show-credentials
11. The original password is still set for VNC

Other Info
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You can also view (or change) the passwords using the Password & Keys app (seahorse).
In the left sidebar, click Passwords> Login and then look for GNOME Remote Desktop RDP credentials and GNOME Remote Desktop VNC password.

System Info
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gnome-control-center 1:42.2-1ubuntu1 (kinetic)