fix docs: Remove unused split import

[colmer]

Remove unused import in vue example

Checklist:

• If this PR contains changes to the library itself (not necessary for e.g. docs updates), please include a changeset (see CONTRIBUTING.md)
• If this PR is a new feature, please reference an issue where a consensus about the design was reached (not necessary for small changes)
• Make sure all of the significant new logic is covered by tests

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[shorgi]

Thanks @colmer!