[5.1] Use update channel the correct way

[bembelimen]

Alternatives for #43184

[LadySolveig]

I have tested this item ✅ successfully on e9e03f8

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[richard67]

@bembelimen It seems this PR breaks the unit tests for the constraint checker.

[laoneo]

Why did you revert the final statement? Sounds logic to me instead of the long description that this class is internal only.

[bembelimen]

I'm not keen to rewrite and fix all the tests, when I declare them as final (plus, I don't like to close classes that way). Feel free to look into it, but I don't plan to do it before the RC.

[LadySolveig]

Thank you!