`actions/setup-node` modifies `pnpm-lock.yaml`.

[kristof-mattei]

Description:
A clear and concise description of what the bug is.

Action version:
53b83947a5a98c8d113130e565377fae1a50d02f # v6.3.0

Platform:

• Ubuntu
• macOS
• Windows

Runner type:

• Hosted
• Self-hosted

Tools version:

    "node": "24.14.1",
    "pnpm": "10.33.0"

Repro steps:
Clone https://github.com/kristof-mattei/pnpm-test/

Locally, do pnpm install, and observe no changes with git diff.

Create new, empty PR, and observe the actions/setup-node action does something that modifies the pnpm-lock.yaml file.

https://github.com/kristof-mattei/pnpm-test/actions/runs/24292198765/job/70931299723?pr=4

Expected behavior:

No modifications to the pnpm-lock.yaml.

Actual behavior:

pnpm-lock.yaml is modified.