Fix: dockerfile cmd for npm and pnpm

[yang-young]

The Dockerfile in the document contained an incorrect npm command that caused build failures during the image creation process.
The error appeared in the following lines:

CMD [ -d "node_modules" ] && npm run start --host 0.0.0.0 --poll 1000 || npm run install && npm run start --host 0.0.0.0 --poll 1000

In npm and pnpm start, --host 0.0.0.0 --poll 1000 are additional parameters. If you need to pass these parameters to the actual script, you must use -- to separate them.

Another problem is that the file path is wrong. In the Dockerfile, it is /opt/docusaurus, but here it is /var/docusaurus.

docker run --rm -d -p 3000:3000 -v $(pwd):/var/docusaurus <tag>

[github-actions]

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[github-actions]

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