Also pin editorconfigchecker by sha

[yubiuser]

What does this PR aim to accomplish?:

Be consistant to pin all actions.

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[Copilot]

Pull Request Overview

This PR enhances security by pinning the editorconfig-checker action to a specific SHA hash instead of using the main branch reference. This change ensures consistent builds and prevents potential security vulnerabilities from upstream changes.

• Replaced the main branch reference with a specific SHA hash for the editorconfig-checker action

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