S3 third-party deps sync workflow: specify correct secrets (#83489)
A followup for: #83306
#83306 used wrong S3 secrets: `AWS_S3_UPDATE_***`, that resulted a failure of the newly added job:
<img width="1228" alt="image" src="https://user-images.githubusercontent.com/108101595/184759049-b4900753-5d29-4352-8704-ce56734be750.png">
The correct secrets to access OSSCI buckets have `AWS_OSSCI_S3_***` prefix.
This PR makes the workflow use the correct secrets.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/83489
Approved by: https://github.com/huydhn, https://github.com/malfet
