Update npx amplify generate config -> outputs - Gen2 doc (#7344)

npx amplify generate config is throwing 
>>Unknown command: config

Generates post deployment artifacts

Commands:
  amplify generate outputs               Generates amplify outputs
  amplify generate forms                 Generates UI forms
  amplify generate graphql-client-code   Generates graphql API code
  amplify generate schema-from-database  Generates typescript data schema from a
                                          SQL database

src/pages/gen2/reference/cli-commands/index.mdx

@@ -185,7 +185,7 @@ npx amplify generate <subcommand> --stack <cloudformation-stack-name>
 npx amplify generate <subcommand> --app-id <app-id> --branch <git-branch-name>
 ```
 
-## npx amplify generate config
+## npx amplify generate outputs
 
 Generate the client configuration file (such as `amplifyconfiguration.json`) for your frontend application to consume. This is intended to be used to manually generate a configuration file for an environment other than your personal cloud sandbox. For example, you might use it if you would like to verify something your coworker is seeing in their cloud sandbox, or to demonstrate frontend changes locally using a pre-existing "staging" branch.
 
@@ -202,15 +202,15 @@ In addition to the required options noted in [`amplify generate`](#amplify-gener
 As mentioned above, you can specify a team member's cloud sandbox CloudFormation stack:
 
 ```bash
-npx amplify generate config --stack amplify-nextamplifygen2-josef-sandbox-ca85e1081b
+npx amplify generate outputs --stack amplify-nextamplifygen2-josef-sandbox-ca85e1081b
 ```
 
 #### Use with mobile applications
 
 Similar to `sandbox`, you can specify an alternate configuration file format by using `--format`:
 
 ```bash
-npx amplify generate config --stack amplify-nextamplifygen2-josef-sandbox-ca85e1081b --format json-mobile
+npx amplify generate outputs --stack amplify-nextamplifygen2-josef-sandbox-ca85e1081b --format json-mobile
 ```
 
 ## npx amplify generate graphql-client-code