[Bugfix]: Installing dev environment due to pydantic incompatible version

[hickeyma]

Update pydantic version to min 2.11.7 for openai-harmony compatibility to fix the following error when installing dev env:

$ uv pip install -r requirements/common.txt -r requirements/dev.txt --torch-backend=auto

  × No solution found when resolving dependencies:
  ╰─▶ Because openai-harmony>=0.0.3 depends on pydantic>=2.11.7 and only the following versions of openai-harmony are available:
          openai-harmony<=0.0.3
          openai-harmony==0.0.4
      we can conclude that openai-harmony>=0.0.3 depends on pydantic>=2.11.7.
      And because you require openai-harmony>=0.0.3 and pydantic==2.11.5, we can conclude that your requirements are unsatisfiable.
(vllm) root@marty-gpu-dev-l40s:/data/dev/github.com/vllm-project/vllm# vim requirements/common.txt 
(vllm) root@marty-gpu-dev-l40s:/data/dev/github.com/vllm-project/vllm# vim requirements/common.txt 
(vllm) root@marty-gpu-dev-l40s:/data/dev/github.com/vllm-project/vllm# uv pip install -r requirements/common.txt -r requirements/dev.txt --torch-backend=auto
  × No solution found when resolving dependencies:
  ╰─▶ Because you require pydantic>=2.11.7 and pydantic==2.11.5, we can conclude that your requirements are unsatisfiable.

Fixes #23352

[gemini-code-assist]

Code Review

This pull request addresses a dependency conflict with pydantic that arises during the installation of the development environment. The changes update the minimum required version of pydantic to 2.11.7 in requirements/common.txt and pin it to the same version in the requirements/test.txt lockfile. This resolves the incompatibility with the openai-harmony package and fixes the installation error. The changes are correct and necessary.

[github-actions]

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[DarkLight1337]

Thanks for fixing!

[hickeyma]

@DarkLight1337 Thanks for reviewing. I don't think this PR is breaking CI.

[DarkLight1337]

Retrying the failing tests