docs(starters): add styled-components starter

[blakenoll]

Description

Modified the default starter to use styled components allowing for a basic way to get up and running with Gatsby and styled components.

[wardpeet]

We put all these frameworks like emotion in the same bucket

Suggested change

	- styled-components
	- Styling:CSS-in-JS

[wardpeet]

You got a linting error 😄

You can run npx prettier --write docs/starters.yml and then commit that file, that should resolve the linting error.

[blakenoll]

@wardpeet Thanks for showing me the fix. I went in and ran prettier and also updated the tag to what you suggested above.

[DSchau]

Thanks for this!

[gatsbot]

Holy buckets, @blakenoll — we just merged your PR to Gatsby! 💪💜

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