[Backport] 2021.1/universal/bugfix/multiedit

[Nzollner]

Purpose of this PR

This is a backport of this PR adding multi-edit to the UniversalRenderPipelineAsset.

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Testing status

This is only a UI change and because of that, I have not started any testing since there should be no changes to the result.

I have tested the multi-edit on my laptop(Windows 10, using DX11).
I tested the multi-edit by checking if I could change the values and if the values change affected the view and if the actions were undoable which they were.

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Comments to reviewers

When you test this check if the values work as expected and if the changes correspond to the visual changes which should be applied with the changed values.

[github-actions]

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