Fix torchrl scripts for PT 2.6 / TorchRL>=0.6 #3588

Job	Run time
pytorch_tutorial_build_worker (1, 15, linux.g5.12xlarge.nvidia.gpu)	15m 59s
pytorch_tutorial_build_worker (2, 15, linux.g5.4xlarge.nvidia.gpu)	43m 12s
pytorch_tutorial_build_worker (3, 15, linux.g5.4xlarge.nvidia.gpu)	21m 40s
pytorch_tutorial_build_worker (4, 15, linux.g5.4xlarge.nvidia.gpu)	32m 13s
pytorch_tutorial_build_worker (5, 15, linux.g5.4xlarge.nvidia.gpu)	22m 12s
pytorch_tutorial_build_worker (6, 15, linux.g5.4xlarge.nvidia.gpu)	21m 26s
pytorch_tutorial_build_worker (7, 15, linux.4xlarge.nvidia.gpu)	22m 47s
pytorch_tutorial_build_worker (8, 15, linux.4xlarge.nvidia.gpu)	14m 25s
pytorch_tutorial_build_worker (9, 15, linux.4xlarge.nvidia.gpu)	20m 22s
pytorch_tutorial_build_worker (10, 15, linux.4xlarge.nvidia.gpu)	18m 39s
pytorch_tutorial_build_worker (11, 15, linux.4xlarge.nvidia.gpu)	15m 28s
pytorch_tutorial_build_worker (12, 15, linux.4xlarge.nvidia.gpu)	33m 54s
pytorch_tutorial_build_worker (13, 15, linux.4xlarge.nvidia.gpu)	46m 6s
pytorch_tutorial_build_worker (14, 15, linux.4xlarge.nvidia.gpu)	35m 12s
pytorch_tutorial_build_worker (15, 15, linux.4xlarge.nvidia.gpu)	28m 39s
pytorch_tutorial_build_manager	22m 44s
	6h 54m 58s

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