Change PK creation in sql cache tool to allow multiple table creations

[BrennanConroy]

You can't create 2 tables in the same database with this tool currently because you get

An error occurred while trying to create the table and index. There is already an object named 'pk_Id' in the database.
Could not create constraint or index. See previous errors.

The second time you try to create a new table.

Changing:
https://github.com/aspnet/DotNetTools/blob/dev/src/Microsoft.Extensions.Caching.SqlConfig.Tools/SqlQueries.cs#L19
to
PRIMARY KEY (Id)
should fix the issue

cc @natemcmaster