[rel/17.6] Filter out known platform sources

[nohwnd]

When default assembly filter in azdo is used, which is test.dll, many of test platform own dlls are included, and when we don't exclude them they are misinterpreted as test assemblies, because we simply try to run whatever user gives us, no matter what the name is. Those dlls are using runnable tfm (e.g. netcoreapp3.1) so we don't know that they should be skipped, and they are not later filtered out by having a missing runtime provider. So these sources try to run, and will fail the run because they have missing runtime config or similar required files.

Related issue

Fix #4511

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