Provide the live PackageOverrides.txt file to SDK when building libraries that target the live targeting pack

[ViktorHofer]

Libraries in runtime that build against the live targeting pack restore with an outdated pruning data state. There's a hook that the SDK added (property) to point to the live PackageOverrides.txt file so that the data doesn't lag behind. We should set that, probably in targetingpacks.targets.

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