return result because @Octol1ttle told me to do so

Signed-off-by: Macintosh II <mctaylxrs@outlook.com>

src/Services/Update/MemberUpdateService.cs

@@ -141,6 +141,8 @@ public sealed partial class MemberUpdateService : BackgroundService
             {
                 data.MutedUntil = null;
             }
+
+            return unmuteResult;
         }
 
         return Result.FromSuccess();