[WIP] Fix pre-push script issue with shallow clone

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

Original prompt

If Github Copilot generates a PR, it attempts to push to a branch. This is successful the first time Copilot pushes to the branch, but subsequent changes end up having a problem with the pre-push script: the EUI pre-push script relies on a full commit history, but the Copilot environment only provides a shallow clone.

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[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 715c5a6
• Documentation website
• Storybook

cc @clintandrewhall @Copilot