fix(plugin-react): return code if should skip in transform (fix #7586)

[ZYSzys]

Description

In transform phase, just return code so that the import React from 'react'; could be injected if shouldSkip is true.

Fixes #7586

Additional context

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[bluwy]

The source code change looks good to me, but it seems like something's up in CI.

[ZYSzys]

The source code change looks good to me, but it seems like something's up in CI.

@bluwy Maybe it's because of the wrong pnpm version, I've changed to pnpm@v7 and CI is successful now.