Centralise logging of non-official builds

osu.Game/OsuGame.cs

@@ -8,7 +8,6 @@ using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
-using System.Reflection;
 using System.Threading;
 using System.Threading.Tasks;
 using Humanizer;
@@ -1055,9 +1054,6 @@ namespace osu.Game
         {
             base.LoadComplete();
 
-            if (RuntimeInfo.EntryAssembly.GetCustomAttribute<OfficialBuildAttribute>() == null)
-                Logger.Log(NotificationsStrings.NotOfficialBuild.ToString());
-
             var languages = Enum.GetValues<Language>();
 
             var mappings = languages.Select(language =>

osu.Game/Updater/UpdateManager.cs

@@ -10,6 +10,7 @@ using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Sprites;
+using osu.Framework.Logging;
 using osu.Game.Configuration;
 using osu.Game.Graphics;
 using osu.Game.Localisation;
@@ -66,9 +67,16 @@ namespace osu.Game.Updater
                 if (FixedReleaseStream != null)
                     config.SetValue(OsuSetting.ReleaseStream, FixedReleaseStream.Value);
 
+                // notify the user if they're using a build that is not officially sanctioned.
                 if (RuntimeInfo.EntryAssembly.GetCustomAttribute<OfficialBuildAttribute>() == null)
                     Notifications.Post(new SimpleNotification { Text = NotificationsStrings.NotOfficialBuild });
             }
+            else
+            {
+                // log that this is not an official build, for if users build their own game without an assembly version.
+                // this is only logged because a notification would be too spammy in local test builds.
+                Logger.Log(NotificationsStrings.NotOfficialBuild.ToString());
+            }
 
             // debug / local compilations will reset to a non-release string.
             // can be useful to check when an install has transitioned between release and otherwise (see OsuConfigManager's migrations).