fix(readme): add destructure import example

[jefrydco]

Since in index.ts we don't export any default module,

shiki/packages/shiki/src/index.ts

Lines 1 to 6 in 58cb92c

	export { getTheme, loadTheme, BUNDLED_THEMES } from 'shiki-themes'
	export { BUNDLED_LANGUAGES } from 'shiki-languages'
	export { getHighlighter } from './highlighter'
	export { renderToHtml } from './renderer'
	export { IThemedToken } from './themedTokenizer'

it would raise an error like this, if we use import shiki from 'shiki' syntax.

The requested module 'file:///<some-path>/node_modules/shiki/dist/index.js' does not provide an export named 'default'

I think it's better to add destructure way to import shiki.

[octref]

Hmm, maybe I should export * as default, what do you think?

That's a bad idea: https://basarat.gitbook.io/typescript/main-1/defaultisbad.
I think it should be import * as shiki from 'shiki' though. Thanks for your contribution.

[octref]

Sorry but I don't really think it clarify anything. TS users should be able to figure this out themselves so I'm removing it.