fix: Correct issue where potentially empty Sandbox is assigned to a deployment.

Author: paulhazen

com.playeveryware.eos/Runtime/Core/Config/ProductConfig.cs

@@ -155,9 +155,9 @@ protected override void OnReadCompleted()
         protected override void BeforeWrite()
         {
             // If there is one deployment, and one sandbox, then make sure they
-            // are linked to each other.
+            // are linked to each other if the sandbox is not empty.
             // But only do this if they have been newly added
-            if (!_deploymentDefined && Environments.Deployments.Count ==1 && Environments.Sandboxes.Count == 1)
+            if (!_deploymentDefined && Environments.Deployments.Count ==1 && Environments.Sandboxes.Count == 1 && !Environments.Sandboxes[0].Value.IsEmpty)
             {
                 Environments.Deployments[0].Value.SandboxId = Environments.Sandboxes[0].Value;
             }