npm install -> npm add (#8022)

Author: josefaidt

src/pages/[platform]/build-a-backend/auth/advanced-workflows/index.mdx

@@ -396,7 +396,7 @@ import {
 } from 'aws-amplify/auth';
 
 // Note: This example requires installing `@aws-sdk/client-cognito-identity` to obtain Cognito credentials
-// npm i @aws-sdk/client-cognito-identity
+// npm add @aws-sdk/client-cognito-identity
 import { CognitoIdentity } from '@aws-sdk/client-cognito-identity';
 
 // You can make use of the sdk to get identityId and credentials

src/pages/[platform]/build-a-backend/data/optimistic-ui/index.mdx

@@ -43,8 +43,8 @@ For more on Amplify Data, see the [API documentation](/[platform]/build-a-backen
 To get started, run the following command in an existing Amplify project with a React frontend:
 
 ```bash title="Terminal" showLineNumbers={false}
-# Install TanStack Query
-npm i @tanstack/react-query @tanstack/react-query-devtools
+npm add @tanstack/react-query && \
+npm add --save-dev @tanstack/react-query-devtools
 ```
 
 Modify your Data schema to use this "Real Estate Property" example:

src/pages/[platform]/build-a-backend/functions/scheduling-functions/index.mdx

@@ -67,7 +67,7 @@ export const handler: EventBridgeHandler<"Scheduled Event", null, void> = async
 **Note**: AWS Lambda types can be installed with
 
 ```bash title="Terminal" showLineNumbers={false}
-npm install --save-dev @types/aws-lambda
+npm add --save-dev @types/aws-lambda
 ```
 
 </Callout>