Firebird: Fix tests in Issues group

- add requirements to test cases which is not supposed to be run on firebird due to lack of support
  of ceratain features
- workaround for certain test cases to have correct expected results
- formatting

Author: alex-kulakov

Orm/Xtensive.Orm.Tests/Issues/Issue0624_EntitySetSubqueryError.cs

@@ -69,7 +69,6 @@ public class Issue0624_EntitySetSubqueryError : AutoBuildTest
   {
     protected override void CheckRequirements()
     {
-      base.CheckRequirements();
       Require.ProviderIsNot(StorageProvider.Oracle | StorageProvider.MySql);
     }
 
@@ -102,6 +101,8 @@ public void Test01()
     [Test]
     public void Test02()
     {
+      Require.AnyFeatureSupported(ProviderFeatures.TemporaryTableEmulation | ProviderFeatures.TemporaryTables);
+
       using (var session = Domain.OpenSession())
       using (var t = session.OpenTransaction()) {
         var controlId = Guid.NewGuid();

Orm/Xtensive.Orm.Tests/Issues/IssueJira0437_OperationsWithListOfInt.cs

@@ -1,6 +1,6 @@
-// Copyright (C) 2013 Xtensive LLC.
-// All rights reserved.
-// For conditions of distribution and use, see license.
+// Copyright (C) 2013-2021 Xtensive LLC.
+// This code is distributed under MIT license terms.
+// See the License.txt file in the project root for more information.
 // Created by: Denis Krjuchkov
 // Created:    2013.02.22
 
@@ -35,21 +35,24 @@ protected override DomainConfiguration BuildConfiguration()
       return configuration;
     }
 
+    protected override void CheckRequirements()
+      => Require.AnyFeatureSupported(ProviderFeatures.TemporaryTableEmulation | ProviderFeatures.TemporaryTables);
+
     protected override void PopulateData()
     {
       using (var session = Domain.OpenSession())
       using (var tx = session.OpenTransaction()) {
-        new NamedObject {Name = "One"};
-        new NamedObject {Name = "Two"};
-        new NamedObject {Name = "Three"};
+        _ = new NamedObject {Name = "One"};
+        _ = new NamedObject {Name = "Two"};
+        _ = new NamedObject {Name = "Three"};
         tx.Complete();
       }
     }
 
     [Test]
     public void GroupJoinTest()
     {
-      Require.AnyFeatureNotSupported(ProviderFeatures.TemporaryTableEmulation | ProviderFeatures.TemporaryTables);
+      Require.AnyFeatureSupported(ProviderFeatures.TemporaryTableEmulation | ProviderFeatures.TemporaryTables);
       using (var session = Domain.OpenSession())
       using (var tx = session.OpenTransaction()) {
         var items = new List<int> {2, 3};
@@ -66,7 +69,7 @@ into j
     [Test]
     public void JoinTest()
     {
-      Require.AnyFeatureNotSupported(ProviderFeatures.TemporaryTableEmulation | ProviderFeatures.TemporaryTables);
+      Require.AnyFeatureSupported(ProviderFeatures.TemporaryTableEmulation | ProviderFeatures.TemporaryTables);
       using (var session = Domain.OpenSession())
       using (var tx = session.OpenTransaction()) {
         var items = new List<int> {1, 2};
@@ -87,7 +90,7 @@ orderby o.Id
     [Test]
     public void ApplyTest()
     {
-      Require.AnyFeatureNotSupported(ProviderFeatures.TemporaryTableEmulation | ProviderFeatures.TemporaryTables);
+      Require.AnyFeatureSupported(ProviderFeatures.TemporaryTableEmulation | ProviderFeatures.TemporaryTables);
       using (var session = Domain.OpenSession())
       using (var tx = session.OpenTransaction()) {
         var items = new List<int> {1, 2, 3};