Remove test fixture attribute from abstract base class

This is to avoid nunit reporting ignored tests for the abstract class.

--HG--
branch : 1.x

src/Orchard.Tests.Modules/Scripting/EvaluatorTestsBase.cs

@@ -4,7 +4,6 @@ using NUnit.Framework;
 using Orchard.Scripting.Compiler;
 
 namespace Orchard.Tests.Modules.Scripting {
-    [TestFixture]
     public abstract class EvaluatorTestsBase {
         [Test]
         public void EvaluateSimpleConstant() {