Update GitHub Actions to checkout@v5 and setup-go@v6

[MamunC0der]

uses: actions/checkout@v3 -> uses: actions/checkout@v5

uses: actions/setup-go@v5.1.0 -> uses: actions/setup-go@v6.0.0

Reason:
These updates provide enhanced caching, better security, and compatibility with recent GitHub runner and Go releases.

Checkout v5 release notes: https://github.com/actions/checkout/releases/tag/v5.0.0
Setup-go v6 release notes: https://github.com/actions/setup-go/releases/tag/v6.0.0

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Note

Update .github/workflows/check.yml to use actions/checkout@v5 and actions/setup-go@v6.0.0.

^{Written by Cursor Bugbot for commit de34fb6. This will update automatically on new commits. Configure here.}

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[cla-assistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}