'Setting up Xcode' in CONTRIBUTING.md

[chrysaora-achlyos]

Describe the bug

The 'Setting up Xcode' section in CONTRIBUTING.md needs more details.

To Reproduce

"After you have cloned all of the Swift Packages the next step is too change the team identifier and bundle identifier in the signing page of the project settings. You should set these to your own values otherwise the project will not build on your system."

These were not sufficent for me. I got other errors on the 'Signing' section.

Errors

An Application Group with identifier 'group.jellycuts' is not available. Pleas enter a different string.
An iCloudContainer with Identifier 'iCloud.Jellycuts' is not available. Please enter a different string.

I had to manually create uniquely named Application Group and iCloudContainer Identifiers on my developer.apple.com Account, and change signing setup page to match my new Identifiers.

Perhaps one also should change the "Keychain Sharing//Keychain Groups" value which is 'com.zlineman.Jellyfish' to match the Bundle Identifier

Additional context

Perhaps this is obvious stuff, but for someone who has not worked in Xcode for several years, or ever, the onboarding via 'Setting up Xcode' could be greatly expanded.

Admittedly these types of error are hard to find unless starting from a clean slate since once you have done on developer.apple.com, the identifiers remain defines.

If you reclone the project to validate an ongoing documenting of the process, the failures will not happen since your developer account will have the Identifiers already created.