Update the flatpak version to the runtime org.gnome.Platform/x86_64/40

[codingepaduli]

Describe the bug
Please, update the flatpak version to the runtime org.gnome.Platform/x86_64/40, as for
flathub / net.christianbeier.Gromit-MPX Issue #1

To Reproduce
Run flatpak update in order to update the Gromit-Mpx version installed.

Expected Behavior

Screenshots

Desktop (please complete the following information):

• OS and version: Debian 10
• Xorg version used: 1:7.7+19
• Wayland version used:

Additional context

[bbhtt]

I opened flathub/net.christianbeier.Gromit-MPX#2, please test whenever the build gets posted. Thanks!

[bk138]

I opened flathub/net.christianbeier.Gromit-MPX#2, please test whenever the build gets posted. Thanks!

Thanks! Left some comments there. :-)

[bk138]

@bbhtt I re-used your commits from flathub/net.christianbeier.Gromit-MPX#2 for this repo here, hope that's OK!