metrics should have an unsafe option

[mfbalin]

🚀 The feature

For high performance low latency use cases, any CPU GPU synchronization kills the performance. The metrics should have an unsafe option assuming all inputs are valid and avoid any synchronization such as here:

torcheval/torcheval/metrics/functional/classification/f1_score.py

Lines 206 to 209 in ea813d3

	if num_label_is_zero.any():
	logging.warning(
	"Warning: Some classes do not exist in the target. F1 scores for these classes will be cast to zeros."
	)

Motivation, pitch

I am developing a high performance GNN library where each iteration can take less than 10ms. Any synchronization kills the performance of my use case.

Alternatives

No response

Additional context

No response