Add Continuation Token Paging Support to the InMemoryRepository<T>

[mumby0168]

We have recently introduced paging into the DefaultRepository<T> but there is not yet support for the continuation token version in the InMemoryRepository<T>. This could return a Guid as the token and just use Skip().Take() under the hood.

[mumby0168]

Hey @robertbennett1998 @IEvangelist

I know Rob you've raised this issue Azure/azure-cosmos-dotnet-v3#2987 around the complications with replicating continuation tokens.

I was wondering what both your thoughts were on doing an implementation of this maybe ignoring some of the complications, as long as we document it?

I came to this thought as if you were using the in-memory repository to test some of these niche cases where a document is inserted mid-page for example, I would say you are doing something wrong, I'd say you should be testing against the real service.

Let me know what you both think.

[robennett2]

I was thinking about this, I think we could do something with hashing the object and saving the index that object was in. This would allow us to replicate that behivour in that thread. I will try to have a look at it it tomorrow night / early next week.

We could do a basic implementation now and document it but it would be frustrating especially if it was implemented at a later date and broke unit tests etc.