test: test SSR after HMR

[hi-ogawa]

Description

I added a test to check ssrLoadModule correctly reflects the same change as client HMR. I verified this fails on 6.0.0-alpha.17 but passes on v5. cc @patak-dev @sheremet-va

Technically this is purely a ssrLoadModule concern (probably I can write a similar failing test without React), but I think it's still nice to test it in the context of React SSR (for example, on RSC framework, it also requires framework side code to make sure server side module is invalidated correctly on top of ssrLoadModule or new module runner).

Additional context

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What is the purpose of this pull request?

• [ ] Bug fix
• [ ] New Feature
• [ ] Documentation update
• [x] Other

Before submitting the PR, please make sure you do the following

• [x] Read the Contributing Guidelines.
• [x] Read the Pull Request Guidelines and follow the PR Title Convention.
• [x] Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• [x] Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• [x] Ideally, include relevant tests that fail without this PR but pass with it.

[ArnaudBarre]

It's already failing! Maybe there is already an issue in v5?

[hi-ogawa]

Oh well, it looks like hmr test is also running in test-build, so it's expected to fail. I added test.skipIf(isBuild) to skip this. https://github.com/vitejs/vite-plugin-react/pull/326/commits/11250e078a21a826fe47cabfcb7a69b187bafb86

The reason why it was passing before is because untilUpdated assertion is actually no-op during build: https://github.com/vitejs/vite-plugin-react/blob/11250e078a21a826fe47cabfcb7a69b187bafb86/playground/test-utils.ts#L92-L97

[ArnaudBarre]

Thanks a lot @hi-ogawa!