Suggest for a polynominal lr_scheduler

### 🚀 The feature, motivation and pitch

A polynominal lr_schduler is useful in multiple task.

### Alternatives

_No response_

### Additional context

https://github.com/cmpark0126/pytorch-polynomial-lr-decay
https://www.tensorflow.org/api_docs/python/tf/keras/optimizers/schedules/PolynomialDecay

Here is a possible useful repo for this issue.

cc @vincentqb @jbschlosser @albanD