updated nb-icons content in installation page

Author: amars29

docs/3.3.x/installation.mdx

@@ -40,7 +40,7 @@ All snippets start with the prefix `nb-` and are followed by the name of the des
 [NativeBase Icons](./nb-icons) was designed to make integration of icons in nativebase projects easier. It is a unified library which export icons and fonts for all the native and web platforms.
 
 ```jsx
-import { Entypo } from "@native-base/icons";
+yarn add @native-base/icons
+```
 
-return <Icon as={Entypo} name="user"></Icon>;
-```
+[Click here](./nb-icons) to see how you can get started with NativeBase Icons in your projects.

docs/next/installation.mdx

@@ -40,7 +40,7 @@ All snippets start with the prefix `nb-` and are followed by the name of the des
 [NativeBase Icons](./nb-icons) was designed to make integration of icons in nativebase projects easier. It is a unified library which export icons and fonts for all the native and web platforms.
 
 ```jsx
-import { Entypo } from "@native-base/icons";
+yarn add @native-base/icons
+```
 
-return <Icon as={Entypo} name="user"></Icon>;
-```
+[Click here](./nb-icons) to see how you can get started with NativeBase Icons in your projects.