We've been trying to do the same for the last weeks and I find no way to properly configure it.
In our case we have Beta and Release. Both configurations with different bundle identifiers:
com.demo.app and com.demo.app.beta.
I've tried to configure the project to use different entitlement files for both the app and the appClip. After a call with an Apple Engineer they told me the way we should use to trick Xcode is using xcconfig files and set user-defined variables to setup the bundle identifiers and to set the parent app bundle id in the entitlement files; and use only entitlement file per target. After configuring everything the same signing errors appear. I feel like it may be a bug in Xcode.
A valid alternative for me would be to be able to configure Xcode to avoid assigning an appClip for the beta configuration, as dmrschmidt2 is pointing out but I think that would be even harder to accomplish.
Topic:
App & System Services
SubTopic:
General
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