caps page metadata.

Author: mxbaylee

api-playground/mdx/authentication.mdx

@@ -21,7 +21,7 @@ The page's authentication method will override mint.json if both are set.
 }
 ```
 
-```md page metadata
+```md Page Metadata
 ---
 title: "Your page title"
 authMethod: "bearer"
@@ -42,7 +42,7 @@ authMethod: "bearer"
 }
 ```
 
-```md page metadata
+```md Page Metadata
 ---
 title: "Your page title"
 authMethod: "basic"
@@ -64,7 +64,7 @@ authMethod: "basic"
 }
 ```
 
-```md page metadata
+```md Page Metadata
 ---
 title: "Your page title"
 authMethod: "key"
@@ -78,7 +78,7 @@ authMethod: "key"
 The "none" authentication method is useful to disable authentication on a specific endpoint after setting a default in mint.json.
 
 <CodeGroup>
-```md page metadata
+```md Page Metadata
 ---
 title: "Your page title"
 authMethod: "none"