fix: wrong url in next/prev button in some cases

[hong4rc]

Motivation

Resolved #1344

Have you read the Contributing Guidelines on pull requests?

Yes

Test Plan

• I clone https://github.com/reduxjs/redux and install all dependencies
• Use this commit for node_modules/docusaurus
• Run yarn start
• Go to http://localhost:3000/faq
• Go to the bottom of the page and click on "General" and it goes to http://localhost:3000/faq/general
• Go to the bottom of the page and click on "FAQ Index" and it goes to http://localhost:3000/faq (it goes to http://localhost:3000/ without this commit)

You can see the preview in https://hongarc.github.io/redux/faq

[docusaurus-bot]

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[docusaurus-bot]

Deploy preview for docusaurus-preview ready!

Built with commit a4a64a8

https://deploy-preview-1488--docusaurus-preview.netlify.com

[endiliey]

@hongarc yes u can remove that line.

[hong4rc]

yes u can remove that line.

Sorry, that is my fault, if I remove that line, .replace(/^\.\.\//, '') can't find ../ (in windows)

[hong4rc]

And I have one way is:

--- .replace('\\', '/')
--- .replace(/^\.\.\//, '')
+++ .replace(new RegExp(`^\\.\\.\\${path.sep}`), '')

It is shorter. Are you want to use it?

[endiliey]

Nah, keep it as it is. Shorter doesn't mean it's more declarative.

[endiliey]

LGTM

Good trick of appending html to make sure faq and faq/general relativeHref is correct

Previously it will be general but after this PR it become ../faq/general.html

[endiliey]

🚀 Ship it ....