[Bugfix] treewide: drop references to librosa

[NickCao]

Purpose

Continuation of #2273

Test Plan

examples/offline_inference/ming_flash_omni/end2end.py
tests/model_executor/models/voxcpm2/test_talker_state_eviction.py

Test Result

TBD

---

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. Please provide the test scripts & test commands. Please state the reasons if your codes don't require additional test scripts. For test file guidelines, please check the test style doc
• The test results. Please paste the results comparison before and after, or the e2e results.
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model. Please run mkdocs serve to sync the documentation editions to ./docs.
• (Optional) Release notes update. If your change is user-facing, please update the release notes draft.

BEFORE SUBMITTING, PLEASE READ https://github.com/vllm-project/vllm-omni/blob/main/CONTRIBUTING.md (anything written below this line will be removed by GitHub Actions)

[chatgpt-codex-connector]

Codex usage limits have been reached for code reviews. Please check with the admins of this repo to increase the limits by adding credits.
Credits must be used to enable repository wide code reviews.

[yuanheng-zhao]

Is this PR a followup fix for #2958 ?

PTAL @linyueqian , @lishunyang12

[NickCao]

Is this PR a followup fix for #2958 ?

#1822 and #2720, the ruff rule should prevent this from happening again.

[linyueqian]

LGTM