docs: make links jump to beginning of the section

[simlmx]

Why

Currently going through the documentation is very annoying since it always bring you back to the big header. Many people have voiced that issue in #1799

What

Here I change the links in the table of content to point to the section (they all have a url pointing to them).
Note that I only "fixed" the links in the table of content, not the inline links of the doc.

Checklist

• Documentation updated
• Demo added
• Ready to be merged

I'm not sure this is the proper approach but it was very straightforward to add.

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[orta]

I was just cloning the repo to make this PR, this should get merged - reading docs by having to scroll through a page of headers each time gets annoying pretty quickly

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spring-animating-auto	Configuration
spring-card	Configuration
spring-cards-stack	Configuration
pmndrs/react-spring	Configuration
pmndrs/react-spring	Configuration
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[joshuaellis]

Looking at the deployment this doesn't work as intended, i think this is because the rehype/remark plug in doesn't use hyphens so use-chain should actually be usechain.

[orta]

No worries, I'll send a new PR with fixed links 👍🏻

[joshuaellis]

closing in favour of #1867