[Misc] fix VLLM_TORCH_PROFILER_DIR to absolute path

[andyxning]

Purpose

VLLM_TORCH_PROFILER_DIR is absolute path according to the comment.

Test Plan

NA

Test Result

NA

(Optional) Documentation Update

NA

Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.

[gemini-code-assist]

Code Review

This pull request aims to fix the handling of VLLM_TORCH_PROFILER_DIR to ensure it's an absolute path. The change from os.path.expanduser to os.path.abspath is a good step, but it introduces a regression by not handling tilde (~) expansion for home directories. My review includes a suggestion to combine both functions to correctly handle all path variations, ensuring the path is both expanded and absolute.

[github-actions]

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