fix: potential small memory leak in ConncectionApprovedMessage (#3486)

This resolves an issue where a very small memory leak could occur within
the `ConnectionApprovedMessage`.

## Changelog

- Fixed: Issue where there was a potential for a small memory leak in
the `ConnectionApprovedMessage`.

## Testing and Documentation

- No tests have been added.
- No documentation changes or additions were necessary.

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## Backport

No backport is needed as this fix is specific to v2.x.

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Author: NoelStephensUnity

com.unity.netcode.gameobjects/CHANGELOG.md

@@ -12,6 +12,8 @@ Additional documentation and release notes are available at [Multiplayer Documen
 
 ### Fixed
 
+- Fixed: Issue where there was a potential for a small memory leak in the `ConnectionApprovedMessage`. (#3486)
+
 ### Changed
 
 ## [2.4.0] - 2025-06-02

com.unity.netcode.gameobjects/Runtime/Messaging/Messages/ConnectionApprovedMessage.cs

@@ -262,6 +262,7 @@ public void Handle(ref NetworkContext context)
                 {
                     NetworkLog.LogWarning($"[Client-{OwnerClientId}] Receiving duplicate connection approved. Client is already connected!");
                 }
+                ConnectedClientIds.Dispose();
                 return;
             }
 
@@ -304,6 +305,9 @@ public void Handle(ref NetworkContext context)
                 }
             }
 
+            // Dispose after it has been used.
+            ConnectedClientIds.Dispose();
+
             // Only if scene management is disabled do we handle NetworkObject synchronization at this point
             if (!networkManager.NetworkConfig.EnableSceneManagement)
             {
@@ -387,7 +391,6 @@ public void Handle(ref NetworkContext context)
                     }
                 }
             }
-            ConnectedClientIds.Dispose();
         }
     }
 }