Understand the increase in OSDC cost

[huydhn]

@zxiiro reports that OSDC clusters on LF account have been overspending. We need to understand why and if that comes from OSDC. According to https://hud.pytorch.org/kpis, there is a 50% increase in the number of PRs to PyTorch in the recent months because contributors are not much more prolific nowadays, so some increase in spending is expected

We also need to know the break down of OSDC cost in compute / storage / traffics, etc so that we can find room to optimize it further

cc @jeanschmidt @zxiiro @jathu

[huydhn]

Another data point we have at hand is the cost dashboard showing CI hours which has been close to double since Jan

[zxiiro]

Let's keep monitoring but it maybe the case that LF has to run at a lower percentage than we used to if CI costs are increasing due to the project getting more contributions than it used to.

[huydhn]

Tracking docs https://docs.google.com/document/d/1iUXxPbrWR-ZtAo7MlpTAD0qlsdqNkN5JnIMEfNFa0v4