Use existing libpipewire in flatpak runtime

[violetmage]

easyeffects bundles an older version of libpipewire to maintain compatability with hosts running pipewire < 0.3

Ubuntu 20.04 LTS is the last major distro with a pipewire < 0.3

Ubuntu 20.04 LTS ends general support at 2025-05-29

Since 20.04 is soon outdated, there is no longer a need to bundle an older libpipewire.

[github-actions]

Workflow failed, but the following artifacts are still available for this pull request:

• easyeffects-archlinux-merge-feac75d4b-into-284af7e59-x86_64.zip

[violetmage]

Closes #3670

[wwmm]

Thanks! Let me ask you something unrelated to this PR. For some time our github action for the Flatpak package has been failing with the error

Build failed: Error: Create Artifact Container failed: The artifact name easyeffects-flatpak-merge-feac75d4b-into-284af7e59-x86_64 is not valid

Do you know what could be causing this? I did not have time to investigate what is going on.

[violetmage]

Looks like this:
actions/upload-artifact#490

edit - fixes available, not merged:

flatpak/flatpak-github-actions#214

flatpak/flatpak-github-actions#215

edit 2 - resolved:
https://github.com/flatpak/flatpak-github-actions/releases/tag/v6.4

flatpak/flatpak-github-actions#217

[wwmm]

I see. So there is nothing we have to do on our side. Just waiting. Thanks!