Fix Application ID

[scx]

Explanation:
https://github.com/flathub/flathub/wiki/AppData-Guidelines#id

The ID should be the same as the App-Requirements#Application-ID:

<!-- Good -->
<id>org.flatpak.qtdemo</id>

<!-- Bad -->
<id>org.flatpak.qtdemo.desktop</id>
<id>qtdemo.desktop</id>

<!-- Incorrect -->
<id>qtdemo</id>

See also:

http://docs.flatpak.org/en/latest/conventions.html#application-ids

As described in Using Flatpak, Flatpak requires each application to have a unique identifier, which has a three-part form such as org.gnome.Dictionary.

http://docs.flatpak.org/en/latest/using-flatpak.html#identifiers

Flatpak identifies each application and runtime using a unique three-part identifier, such as com.company.App. The final segment of this address is the object’s name, and the preceding part identifies the developer, so that the same developer can have multiple applications, like com.company.App1 and com.company.App2.

[mitya57]

Thanks!