docs: fix markup for warnings (#946)

Author: slevithan

docs/guide/compat.md

@@ -4,7 +4,7 @@ outline: deep
 
 # Compatibility Build
 
-::: warn
+::: warning
 This is a compatibility build for v0.x users. And this package is no longer maintained since v3. Please migrate to the latest version.
 :::
 

docs/guide/regex-engines.md

@@ -87,7 +87,7 @@ const jsEngine = createJavaScriptRegexEngine({
 
 Instead of compiling regular expressions on-the-fly, we also provide pre-compiled languages for the JavaScript engine to further reduce startup time.
 
-::: warn
+::: warning
 Pre-compiled languages are not yet supported, due to a [known issue](https://github.com/shikijs/shiki/issues/918) that affects many languages. Please use with caution.
 :::