Raise more verbose warning for gradient scaling in scheduler/optimizer case

[SkafteNicki]

What does this PR do?

Fixes #21339
Fixes #5558

This is both a new and old issue. When gradient scaling is applied, optimizer.step() may be skipped if nan or inf is detected, and the learning rate scheduler detects that the optimizer didn’t step, which results in the warning that users are seeing. There is really nothing we can do to solve this, it requires some effort on the Pytorch side:
pytorch/pytorch#67590
but it has no activity for 4 years. This PR is an attempt at at least provide a bit more verbose output to the end user.

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📚 Documentation preview 📚: https://pytorch-lightning--21426.org.readthedocs.build/en/21426/

[GdoongMathew]

Suggested change

	if "lr_scheduler.step()" in msg and "optimizer.step()" in msg:
	if "Detected call of `lr_scheduler.step()` before `optimizer.step()`." in msg:

There's another warning (here) that fit in the original if statement. The proposed one should be more specific.