Default commit signing system uses incorrect committer for web-flow GPG key

[jarrodldavis]

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After figuring out the issue I had in Codespaces with SSH key signing, I was able to successfully sign a commit using the default signing setup in Codespaces (although it's a bit weird when creating a Codespace from a repo you don't own with the intent to fork). Unfortunately, the commit appears to not use the web-flow user as the committer, which causes such a signed commit to be marked as unverified since I, naturally, don't have the web-flow GPG public key in my GPG settings. Adding the public key to my settings also doesn't work since the email address doesn't match up.