Codesign Mac OS release with developer certificate

[AezNwBrZ6]

Wire version: 3.17.3666
Operating system: macOS

What steps will reproduce the problem?

1. Download pkg from https://github.com/wireapp/wire-desktop/releases/tag/macos%2F3.17.3666
2. MacOS prompted that it's not code signed.

I understand that this prompt can be easily bypassed and that I can and do verify the shasum and PGP signature. However, it's not feasible to teach my friends PGP when I want to convert them to wire. I do not encourage them to use Mac App Store for privacy reasons.

What is the expected result?

Github release should be code signed https://developer.apple.com/support/code-signing/

What is the actual result?
Github release is not code signed. Only Mac App Store release is code signed