Runtime tests for NativeAOT send unnecessary files in Helix payloads

[filipnavara]

For example, runfo get-helix-payload -j 765efa6c-eb36-4098-a2b6-81c33985c105 -w Methodical_d2 -o helix3 downloads a workitem with 184 .dll files (~3 Mb). NativeAOT mostly needs only the .exe files and not the intermediate managed .dll files. We could save time and storage by not including the managed .dll files.

[dotnet-policy-service]

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