Update dependency pyarrow to v18

[RKIMetadataExchange]

This PR contains the following updates:

Package	Type	Update	Change
pyarrow	project.dependencies	major	>=17.0.0,<18 -> >=18,<19

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• If you want to rebase/retry this PR, check this box

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This PR has been generated by Renovate Bot.

[RKIMetadataExchange]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
• you rename this PR's title to start with "rebase!" to trigger it manually

The artifact failure details are included below:

File name: pdm.lock

Command failed: pdm update --no-sync --update-eager pyarrow
WARNING: Project requires a python version of <3.13,>=3.11, The virtualenv is being created for you as it cannot be matched to the right version.
INFO: python.use_venv is on, creating a virtualenv for this project...
Virtualenv is created successfully at /tmp/renovate/repos/github/robert-koch-institut/mex-common/.venv
[FileNotFoundError]: [Errno 2] No such file or directory: '/home/ubuntu/.local/state'
WARNING: Add '-v' to see the detailed traceback