Do not run integration tests in parallel

This fixes the mysterious failing tests when running from the command line.

Author: gmarz

build/scripts/Testing.fsx

@@ -73,7 +73,7 @@ module Tests =
             |> Seq.map Paths.Quote
             |> Seq.iter(fun project -> 
                 Tooling.DotNet.Exec runtime TestFailure "." ["restore"; project;]
-                Tooling.DotNet.Exec runtime TestFailure "." ["test"; project; "-xml"; Paths.Output("TestResults.xml")]) 
+                Tooling.DotNet.Exec runtime TestFailure "." ["test"; project; "-parallel"; parallelization; "-xml"; Paths.Output("TestResults.xml")]) 
 
     let RunUnitTests() =
         !! Paths.Source("Tests/project.json")