Fix a failing test for SQL Server CE (#3488)

Author: fredericDelaporte

src/NHibernate.Test/Async/NHSpecificTest/GH3474/Fixture.cs

@@ -50,6 +50,12 @@ protected override void OnTearDown()
 			transaction.Commit();
 		}
 
+		protected override bool AppliesTo(Dialect.Dialect dialect)
+		{
+			// Polymorphic updates require support of temp tables.
+			return Dialect.SupportsTemporaryTables;
+		}
+
 		[Test]
 		public async Task PolymorphicUpdateShouldNotCommitAsync()
 		{

src/NHibernate.Test/NHSpecificTest/GH3474/Fixture.cs

@@ -38,6 +38,12 @@ protected override void OnTearDown()
 			transaction.Commit();
 		}
 
+		protected override bool AppliesTo(Dialect.Dialect dialect)
+		{
+			// Polymorphic updates require support of temp tables.
+			return Dialect.SupportsTemporaryTables;
+		}
+
 		[Test]
 		public void PolymorphicUpdateShouldNotCommit()
 		{