Issue
Title: Add aws_security_token to credentials file keys
Description
Description of changes: Backport of #10152 to CLIv1.
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Task
Modify the repository so that the issue described above is resolved. The repository is checked out at base commit 95c949f94c2e. Edit files in place; the verifier captures your changes via git diff and scores them against an oracle patch using SWE-RL-style diff-similarity reward.