turn blockquotes into notes (#342)

Author: Rich-Harris

apps/svelte.dev/content/blog/2023-09-20-runes.md

@@ -46,7 +46,7 @@ We don't yet have a release date for Svelte 5. What we're showing you here is a
 
 ## What are runes?
 
-> **rune** /ro͞on/ _noun_
+> [!NOTE] **rune** /ro͞on/ _noun_
 >
 > A letter or mark used as a mystical or magic symbol.
 
@@ -151,7 +151,7 @@ export function createCounter() {
 </button>
 ```
 
-> Outside `.svelte` components, runes can only be used in `.svelte.js` and `.svelte.ts` modules.
+> [!NOTE] Outside `.svelte` components, runes can only be used in `.svelte.js` and `.svelte.ts` modules.
 
 Note that we're using a [get property](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get) in the returned object, so that `counter.count` always refers to the current value rather than the value at the time the function was called.