fix: export-notes command should wait until networkidle

[KermanX]

fix #1897

[netlify]

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[pkg-pr-new]

Open in Stackblitz

create-slidev

pnpm add https://pkg.pr.new/slidevjs/slidev/create-slidev@1898

create-slidev-theme

pnpm add https://pkg.pr.new/slidevjs/slidev/create-slidev-theme@1898

@slidev/client

pnpm add https://pkg.pr.new/slidevjs/slidev/@slidev/client@1898

@slidev/parser

pnpm add https://pkg.pr.new/slidevjs/slidev/@slidev/parser@1898

@slidev/cli

pnpm add https://pkg.pr.new/slidevjs/slidev/@slidev/cli@1898

@slidev/types

pnpm add https://pkg.pr.new/slidevjs/slidev/@slidev/types@1898

commit: 17f6e6b