Further async changes (#387)

* Further async changes
- SaveServer & Backup Server are now async
- Anything that ties in with SaveServer saving (Such as callbacks) are now async
- Various async util methods added
- Removed two wrapper methods and switched code over to use the actual method

* Update test

Libraries/SPTarkov.Server.Core/Controllers/PrestigeController.cs

@@ -59,7 +59,7 @@ public class PrestigeController(
     ///     </list>
     /// </summary>
     /// <returns></returns>
-    public void ObtainPrestige(
+    public async Task ObtainPrestige(
         string sessionId,
         ObtainPrestigeRequestList request)
     {
@@ -75,7 +75,7 @@ public class PrestigeController(
             profile.SptData.PendingPrestige = pendingPrestige;
             profile.ProfileInfo.IsWiped = true;
 
-            _saveServer.SaveProfile(sessionId);
+            await _saveServer.SaveProfileAsync(sessionId);
         }
     }
 }