Web components: Fix code indents

[mejiaj]

Try guidance below to fix indentation in StorybookJS code samples.

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FYI, I got this working on the MD WDS project I'm working on!

Here are my notes on the workaround:
storybookjs/storybook#8078 (comment)

Originally posted by @caseywatts in #14 (comment)

[deebloo]

Another solution would be to use something like js-beautify rather then needing multiple versions of prettier.

https://github.com/Noctua-Technology/uswds/blob/main/.storybook/preview.mjs#L8