example: fix npm/yarn install/run instructions (#10023)

**npm** section currently shows both npm and yarn, while **yarn** section shows just npm.

examples/with-higher-order-component/README.md

@@ -30,16 +30,13 @@ Install it and run:
 ```bash
 npm install
 npm run dev
-# or
-yarn
-yarn dev
 ```
 
 **yarn**
 
 ```bash
-npm install
-npm run dev
+yarn
+yarn dev
 ```
 
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