Add unit tests for Script and Style tag helpers

[Skrypt]

We need to add unit test to test for these:

A script or a style tag that has a type="module" param should not spread it to it's set script dependencies.
A script or a style tag that has a At="Footer" should spread to it's dependencies (Location on tag helper).

Example of ScriptTagHelper unit test: https://github.com/dotnet/aspnetcore/blob/main/src/Mvc/Mvc.TagHelpers/test/ScriptTagHelperTest.cs

Did start working on it last night based on that file.

[Piedone]

Related: #15438.

[github-actions]

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