Update GStreamer to 1.20.4

[flathubbot]

Started test build 1869

[flathubbot]

Build 1869 failed

[flathubbot]

Started test build 1874

[flathubbot]

Build 1874 failed

[barthalion]

bot, build

[flathubbot]

Queued test build for org.gnome.Totem.Devel.

[flathubbot]

Started test build 3377

[flathubbot]

Build 3377 failed

[hadess]

bot, build

[flathubbot]

Queued test build for org.gnome.Totem.Devel.

[flathubbot]

Started test build 5757

[flathubbot]

Build 5757 failed

[flathubbot]

Started test build 5758

[flathubbot]

Build 5758 failed

[hadess]

https://github.com/flathub/flatpak-builder-lint/issues/54 isn't fixed in Flathub:

{
    "errors": [
        "finish-args-redundant-device-all"
    ]
}
If you think problems listed above are a false positive, please report it here:
  https://github.com/flathub/flatpak-builder-lint

[hadess]

bot, build

[flathubbot]

Queued test build for org.gnome.Totem.Devel.

[flathubbot]

Started test build 6148

[flathubbot]

Build 6148 successful To test this build, install it from the testing repository:

flatpak install --user https://dl.flathub.org/build-repo/118595/org.gnome.Totem.Devel.flatpakref