ExpandoObject exceptions during Rebus.SqlServer initialization

[ADD-David-Antolin]

When Rebus.SqlServer is initialized, the following exception occurs in background (although it does not stop the initialization).

Microsoft.CSharp.RuntimeBinder.BinderException:
''System.Dynamic.ExpandoObject' does not contain a definition for 'TABLE_SCHEMA''

followed by

Microsoft.CSharp.RuntimeBinder.BinderException:
''System.Dynamic.ExpandoObject' does not contain a definition for 'TABLE_NAME''

The error is produced here:
https://github.com/rebus-org/Rebus.SqlServer/blob/master/Rebus.SqlServer/SqlServer/SqlServerMagic.cs#L31

I think the use of dynamic and ExpandoObject is unnecessary here:

https://github.com/rebus-org/Rebus.SqlServer/blob/master/Rebus.SqlServer/SqlServer/SqlServerMagic.cs#L104-L108

and can be substituted with a Dictionary<string, string>.