Single Database Multi-Tenant Example is Intentionally Incomplete

In the `An example solution (single database)` section of this page, it states that the callbacks have been omitted for clarity. In my opinion, it is actually more confusing to have the events in the interface, but not show how to implement/use them.

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#### Document Details

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* ID: bb29a2b6-c401-287f-2da9-1aeb3c633b41
* Version Independent ID: bb29a2b6-c401-287f-2da9-1aeb3c633b41
* Content: [Multi-tenancy - EF Core](https://learn.microsoft.com/en-us/ef/core/miscellaneous/multitenancy)
* Content Source: [entity-framework/core/miscellaneous/multitenancy.md](https://github.com/dotnet/EntityFramework.Docs/blob/main/entity-framework/core/miscellaneous/multitenancy.md)
* Product: **entity-framework**
* Technology: **entity-framework-core**
* GitHub Login: @JeremyLikness
* Microsoft Alias: **jeliknes**