[doc] added docusaurus-based version control

[FrankLeeeee]

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Fixed #2655

📝 What does this PR do?

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This PR added docusaurus files to control the website behaviour and versions.

• sidebars.js: this is a file for the sidebar for each version.
• version.js: the website will only render documents for versions included in this file in the main branch. That means you can control the versions shown on the website in the main branch without a release.

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