DynamoDBStorageOptions ServiceId default

[cliedeman]

Dynamodb Grain Storage ServiceId does not default to default as expected.

https://github.com/dotnet/orleans/blob/v10.0.1/src/AWS/Orleans.Persistence.DynamoDB/Options/DynamoDBStorageOptions.cs#L13

This will be covered up if you the cofiguration (aspire style) but can cause unexpected behaviour otherwise

[ReubenBond]

Well, that's unfortunate. Thanks for reporting, @cliedeman! I'm wary of changing this now, but perhaps we can add a validation to force people to set it explicitly in an upcoming release. What do you think, @cliedeman?

[cliedeman]

I think thats reasonable.

Luckily I caught this before release but it wasn't obvious to me that my grain keys all being prefixed with an underscore was a bug.

Ciaran