fix: misleading doc comment

[antews]

Motivation

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Change Summary

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• The PR title adheres to the conventional commits standard
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Additional Context

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PR-Codex overview

This PR updates the documentation and constructor of the Migration contract to clarify the purpose of the _initialOwner parameter, indicating its use in Guardians rather than as a migrator.

Detailed summary

• Updated the documentation for the _initialOwner parameter to specify its use in Guardians.
• Changed the constructor to reflect the new understanding of _initialOwner as related to Guardians.

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