AutoPkg does not read GITHUB TOKEN from default path on fresh setup

[jgstew]

THIS IS ONLY INTENDED FOR AUTOPKG BETAS.

Describe the problem

When running AutoPkg with a blank preference file, I expect the GitHub token to be read from the default path, but it is not.

Preferences contents
BE SURE TO SANITIZE ANY SENSITIVE DATA SUCH AS PASSWORDS OR ADDRESSES.

N/A

AutoPkg output
BE SURE TO SANITIZE ANY SENSITIVE DATA SUCH AS PASSWORDS OR ADDRESSES.

https://github.com/autopkg/autopkg/actions/runs/6318712264/job/17158298776?pr=897#step:11:51

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Ran 93 tests in 9.198s
autopkg search is temporarily disabled; we are migrating to a new strategy in the next release.

In the meantime, please see https://github.com/autopkg/autopkg/wiki/Finding-Recipes for tips on searching GitHub.com directly.
FAILED (failures=1, skipped=6)
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Expected behavior
A clear and concise description of what you expected to happen. What specific part of the recipe or AutoPkg run did not behave correctly?

Version (please complete the following information):

• OS version: all
• AutoPkg Version: 3.0.0RC2