[Bug]: Flatpak package uses out-of-date runtime

[kemelzaidan]

Description of the bug

The flatpak installation method (the only official one, so far) is showing an outdated runtime. It would be interesting to update it, since it can scare most users.

In flathub:

In the cli:

Info: runtime org.kde.Platform branch 6.5 is end-of-life, with reason:
   We strongly recommend moving to the latest stable version of the Platform and SDK
Info: applications using this runtime:
   com.librumreader.librum

Info: runtime org.freedesktop.Platform.VAAPI.Intel branch 22.08 is end-of-life, with reason:
   org.freedesktop.Platform 22.08 is no longer receiving fixes and security updates. Please update to a supported runtime version.
Info: applications using this runtime:
   com.librumreader.librum

Info: runtime org.freedesktop.Platform.GL.default branch 22.08-extra is end-of-life, with reason:
   org.freedesktop.Platform 22.08 is no longer receiving fixes and security updates. Please update to a supported runtime version.
Info: applications using this runtime:
   com.librumreader.librum

Info: runtime org.freedesktop.Platform.GL.default branch 22.08 is end-of-life, with reason:
   org.freedesktop.Platform 22.08 is no longer receiving fixes and security updates. Please update to a supported runtime version.
Info: applications using this runtime:
   com.librumreader.librum

Steps To Reproduce

Try to install the flatpak package from flathub.

Additional Information

No response