Update mock RulesetInfo usage to set OnlineID instead of ID

osu.Game.Tests/Testing/TestSceneRulesetDependencies.cs

@@ -70,7 +70,7 @@ namespace osu.Game.Tests.Testing
             {
                 // temporary ID to let RulesetConfigCache pass our
                 // config manager to the ruleset dependencies.
-                RulesetInfo.ID = -1;
+                RulesetInfo.OnlineID = -1;
             }
 
             public override IResourceStore<byte[]> CreateResourceStore() => new NamespacedResourceStore<byte[]>(TestResources.GetStore(), @"Resources");