test: replace resolve.alias/customResolver with plugin resolveId

[hi-ogawa]

Description

As par vitejs/vite#21476, Vite 8 beta emits a following in stderr and CI is failing. https://github.com/vitest-dev/vitest/actions/runs/21734309219/job/62695879025?pr=9597#step:8:1671

`resolve.alias` contains an alias with `customResolver` option. This is deprecated and will be removed in Vite 9. Please use a custom plugin with a resolveId hook instead.

This PR replaced this.

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