Deltachat-desktop: [Progress] Release 1.15.4 / 1.15.5

[Simon-Laux]

• [X] website (https://github.com/deltachat/deltachat-pages/commit/f05845154732a6c13a351eef45cc369ba069f1a8)
• [ ] flathub (https://github.com/flathub/chat.delta.desktop/pull/52)
• [X] github release (https://github.com/deltachat/deltachat-desktop/releases/tag/v1.15.4)
• [X] mac store
• [Pending] windows store
• [X] homebrew (Homebrew/homebrew-cask#102527)

[cwerner1]

homebrew pull requested ( https://github.com/Homebrew/homebrew-cask/pull/102527 )

[cwerner1]

homebrew pull request for 1.15.5 https://github.com/Homebrew/homebrew-cask/pull/102765

[Simon-Laux]

I think we can close this, there won't be a flatpak release for 1.15.
1.20.2 will have flatpak again and it's progress is tracked in #2276