add support for pnpm lockfile v9.0 mapping to pnpm v10

[a-schur]

What are you trying to accomplish?

respect the version constraint and install the correct version of pnpm, dont fall back to the lockfile version guessed version

new constants of pnpm versions need to be added and mapping logic needs updating

this is a fix for 13045

Anything you want to highlight for special attention from reviewers?

How will you know you've accomplished your goal?

Added support for pnpm lockfile version 9.0 created a test that verifies pnpm lockfile version 9.0 maps to pnpm runtime version 10.

Added test fixtures - created a test fixture file (pnpm_lock_9.0_content.json) that simulates a GitHub API response containing a pnpm-lock.yaml file with lockfileVersion 9.0.

Extended version mapping logic test ensures that when Dependabot encounters a pnpm-lock.yaml file with lockfileVersion 9.0, it correctly determines it needs to use pnpm version 10+ to handle the update process.

Checklist

• I have run the complete test suite to ensure all tests and linters pass.
• I have thoroughly tested my code changes to ensure they work as expected, including adding additional tests for new functionality.
• I have written clear and descriptive commit messages.
• I have provided a detailed description of the changes in the pull request, including the problem it addresses, how it fixes the problem, and any relevant details about the implementation.
• I have ensured that the code is well-documented and easy to understand.