style

Removing the System.Text from StringBuilder since System.Text is included in a using directive.

Author: NoelStephensUnity

com.unity.netcode.gameobjects/TestHelpers/Runtime/NetcodeIntegrationTest.cs

@@ -1783,7 +1783,7 @@ private void UnloadRemainingScenes()
             }
         }
 
-        private System.Text.StringBuilder m_WaitForLog = new System.Text.StringBuilder();
+        private StringBuilder m_WaitForLog = new StringBuilder();
 
         private void LogWaitForMessages()
         {