docs: use optional chaining for `app.dock` (#46119)

docs: use optional chaining for app.dock

docs/api/dock.md

@@ -9,7 +9,7 @@ The following example shows how to bounce your icon on the dock.
 
 ```js
 const { app } = require('electron')
-app.dock.bounce()
+app.dock?.bounce()
 ```
 
 ### Instance Methods

docs/fiddles/features/macos-dock-menu/main.js

@@ -24,9 +24,7 @@ const dockMenu = Menu.buildFromTemplate([
 ])
 
 app.whenReady().then(() => {
-  if (process.platform === 'darwin') {
-    app.dock.setMenu(dockMenu)
-  }
+  app.dock?.setMenu(dockMenu)
 }).then(createWindow)
 
 app.on('window-all-closed', () => {

docs/tutorial/macos-dock.md

@@ -50,9 +50,7 @@ const dockMenu = Menu.buildFromTemplate([
 ])
 
 app.whenReady().then(() => {
-  if (process.platform === 'darwin') {
-    app.dock.setMenu(dockMenu)
-  }
+  app.dock?.setMenu(dockMenu)
 }).then(createWindow)
 
 app.on('window-all-closed', () => {