Replace patch-desktop-filename with patch-electron-desktop-filename

[JakobDev]

patch-desktop-filename is deprecated and will be removed in 26.08. It's replaced by patch-electron-desktop-filename. See flathub/org.electronjs.Electron2.BaseApp#65 for details.

I can confirm that it starts. I didn't test further, as I don't use Slack.

Note:
I needed to disable the integrity check, as the checksum for focusassist.node does not match.

[flathubbot]

🚧 Test build enqueued.

[flathubbot]

🚧 Started test build.

[flathubbot]

✅ Test build succeeded. To test this build, install it from the testing repository:

flatpak install --user https://dl.flathub.org/build-repo/269040/com.slack.Slack.flatpakref

Built for x86_64 architecture.

⚠️ Linter warnings:

Warnings can be promoted to errors in the future. Please try to resolve them.

• 'module-lsb_release-source-git-no-commit-with-tag' warning found in linter manifest check.