[Tables] Support existing edm types in an entity

[annatisch]

If an entity passed into create_entity or upsert_entity has already been formatted with EDM type information, we should directly pass this through to the service.

[annatisch]

Adding some clarifying detail here:
Currently the API prioritizes usability with Python type system. This means we will automatically convert Python types into the EdmType equivalent. For example, if a user provides the following entity definition:

entity = {
    "PartitionKey": "Foo",
    "RowKey": "Bar",
    "CreatedOn": datetime.now()
}
client.create_entity(entity)

Then the SDK serializer will automatically convert the payload into:

{
    "PartitionKey": "Foo",
    "RowKey": "Bar",
    "CreatedOn": "2022-10-31T00:00:00Z",
    "CreatedOn@odata.type": "Edm.Datetime"
}

However, it's possible that a customer has loaded entities from a non-Python-typed source, and those inputs may already have odata.type tags. Therefore we should also support this as input:

entity = {
    "PartitionKey": "Foo",
    "RowKey": "Bar",
    "CreatedOn": "2022-10-31T00:00:00Z",
    "CreatedOn@odata.type": "Edm.Datetime"
}
client.create_entity(entity)

And this payload will be passed directly through to the REST API unaltered.

[github-actions]

Hi @annatisch, we deeply appreciate your input into this project. Regrettably, this issue has remained inactive for over 2 years, leading us to the decision to close it. We've implemented this policy to maintain the relevance of our issue queue and facilitate easier navigation for new contributors. If you still believe this topic requires attention, please feel free to create a new issue, referencing this one. Thank you for your understanding and ongoing support.