Please provide an OwnsMany seeding example

EFCore keeps complaining about unset properties etc.

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#### Document Details

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* ID: fc418ab9-0592-f610-e751-40cb501220da
* Version Independent ID: 822e8923-2647-f573-0c74-66af903776d8
* Content: [Data Seeding - EF Core](https://docs.microsoft.com/en-us/ef/core/modeling/data-seeding#feedback)
* Content Source: [entity-framework/core/modeling/data-seeding.md](https://github.com/dotnet/EntityFramework.Docs/blob/master/entity-framework/core/modeling/data-seeding.md)
* Product: **entity-framework**
* Technology: **entity-framework-core**
* GitHub Login: @AndriySvyryd
* Microsoft Alias: **ansvyryd**