Grant upload-stats jobs access to S3 (#107717)
These jobs have write access to S3 when they are running on our self-hosted runners. On the other hand, they would need the AWS credential to run if they are run on GitHub ephemeral runner.
### Testing
Use the AWS credential in upload-stats environment to run the test command successfully (currently failing in trunk due to the lack of permission https://hud.pytorch.org/pytorch/pytorch/commit/a5f83245fd2e8ff0bc38c058fded4667aacc3330)
```
python3 tools/alerts/upload_alerts_to_aws.py --alerts '[{"AlertType": "Recurrently Failing Job", "AlertObject": "Upload Alerts to AWS/Rockset / upload-alerts", "OncallTeams": [], "OncallIndividuals": [], "Flags": [], "sha": "c8a6c74443f298111fd6568e2828765d87b69c98", "branch": "main"}, {"AlertType": "Recurrently Failing Job", "AlertObject": "inductor / cuda12.1-py3.10-gcc9-sm86 / test (inductor_torchbench, 1, 1, linux.g5.4xlarge.nvidia.gpu)", "OncallTeams": [], "OncallIndividuals": [], "Flags": [], "sha": "f13101640f548f8fa139c03dfa6711677278c391", "branch": "main"}, {"AlertType": "Recurrently Failing Job", "AlertObject": "slow / linux-focal-cuda12.1-py3.10-gcc9-sm86 / test (slow, 1, 2, linux.g5.4xlarge.nvidia.gpu)", "OncallTeams": [], "OncallIndividuals": [], "Flags": [], "sha": "6981bcbc35603e5d8ac7d00a2032925239009db5", "branch": "main"}]' --org "pytorch" --repo "pytorch"
Writing 138 documents to S3
Done!
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/107717
Approved by: https://github.com/clee2000
