How to reproduce:
1. Open the attached project
2. Open the Build Settings (File->Build Settings)
3. Enable the 'Create Xcode Project' option
4. Make a build
5. Open the Xcode project
6. In the Xcode editor, try to archive the project (Product->Archive)
7. Inspect the 'Buildtime' console

Expected result: Build is successful
Actual result: 'The linked and embedded library 'UnityPlayer.dylib' is missing one or more architectures required by this target: arm64.' error is thrown

Reproducible with: 2019.4.28f1
Not reproducible with: 2020.3.10f1, 2021.1.11f1, 2021.2.0a20 (ARM64 Platform is available in Build Settings and gets included)
Couldn't test with: 2018.4.36f1 (Couldn't create an Xcode project)

Note:
- Tested with Xcode 12.2