Merge pull request #10127 from electron/fix-heading-levels-for-class-docs

fix heading levels for class docs

docs/api/browser-view.md

@@ -1,4 +1,4 @@
-# Class: BrowserView
+## Class: BrowserView
 
 > Create and control views.
 

docs/api/menu.md

@@ -1,4 +1,5 @@
-# Class: Menu
+## Class: Menu
+
 
 > Create native application menus and context menus.
 

docs/api/touch-bar.md

@@ -1,4 +1,4 @@
-# Class: TouchBar
+## Class: TouchBar
 
 > Create TouchBar layouts for native macOS applications