[4/4] Deprecate GPUStatsMonitor and XLAStatsMonitor

[daniellepintz]

What does this PR do?

Deprecates GPUStatsMonitor and XLAStatsMonitor, as they can now be replaced by the DeviceStatsMonitor which calls get_device_stats on the Accelerator interface.

Fixes PyTorchLightning#9032

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[daniellepintz]

Closing in favor of Lightning-AI#9924