Pass through VSCODE_IPC_HOOK_CLI to brew edit

[wheelerlaw]

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More information about the background of this PR can be found in this discussion.

This PR preserves the VSCODE_IPC_HOOK_CLI environment variable when running EDITOR=code brew edit ... so that VS Code can use that environment variable during remote development.

[MikeMcQuaid]

Makes sense, thanks @wheelerlaw!