cull(engine-cleanup): pass-8 phase-2 cascade round 1 after GachaUI stub

SVSim.BattleEngine/Shim/UnityEngine/UnityShim.cs

@@ -341,7 +341,6 @@ public void Play(int hash, int layer, float normalizedTime) { }
         public Rect pixelRect { get; set; }
         public Color backgroundColor { get; set; }
         public CameraClearFlags clearFlags { get; set; }
-        public RenderTexture targetTexture { get; set; }
         public Vector3 ViewportToWorldPoint(Vector3 p) => p;
         public Vector3 WorldToViewportPoint(Vector3 p) => p;
         public Vector3 ScreenToWorldPoint(Vector3 p) => p;