Update how to enable Swift Package Manager instructions

Author: loic-sharma

src/_includes/docs/swift-package-manager/how-to-enable-disable.md

@@ -1,7 +1,6 @@
 ## How to turn on Swift Package Manager
 
-Flutter's Swift Package Manager support is turned off by default.
-To turn it on:
+Swift Package Manager is available on the `main` channel:
 
 1. Switch to Flutter's `main` channel:
 
@@ -15,12 +14,6 @@ To turn it on:
    flutter upgrade
    ```
 
-3. Turn on the Swift Package Manager feature:
-
-   ```sh
-   flutter config --enable-swift-package-manager
-   ```
-
 Using the Flutter CLI to run an app modifies the project to add Swift Package
 Manager integration.
 This makes your project download the Swift packages that

src/content/packages-and-plugins/swift-package-manager/for-app-developers.md

@@ -29,8 +29,6 @@ If you find a bug in Flutter's Swift Package Manager support,
 [Swift packages]: https://swiftpackageindex.com/
 [open an issue]: {{site.github}}/flutter/flutter/issues/new?template=2_bug.yml
 
-{% include docs/swift-package-manager/how-to-enable-disable.md %}
-
 ## How to add Swift Package Manager integration
 
 ### Add to a Flutter app
@@ -138,6 +136,8 @@ To undo this migration:
 
 [Turn off Swift Package Manager]: /packages-and-plugins/swift-package-manager/for-app-developers/#how-to-turn-off-swift-package-manager
 
+{% include docs/swift-package-manager/how-to-enable-disable.md %}
+
 ## How to use a Swift Package Manager Flutter plugin that requires a higher OS version
 
 If a Swift Package Flutter Manager plugin requires a higher OS version than

src/content/packages-and-plugins/swift-package-manager/for-plugin-authors.md

@@ -30,8 +30,6 @@ If you find a bug in Flutter's Swift Package Manager support,
 [Swift packages]: https://swiftpackageindex.com/
 [open an issue]: {{site.github}}/flutter/flutter/issues/new?template=2_bug.yml
 
-{% include docs/swift-package-manager/how-to-enable-disable.md %}
-
 ## How to add Swift Package Manager support to an existing Flutter plugin
 
 This guide shows how to add Swift Package Manager support to a plugin that
@@ -47,7 +45,6 @@ migrated to Swift Package Manager yet.
 Plugins that don't support Swift Package Manager can cause problems for projects
 that have migrated.
 
-
 {% tabs %}
 {% tab "Swift plugin" %}
 
@@ -153,3 +150,5 @@ To update your unit tests:
 8. Ensure tests pass **Product > Test**.
 
 [library type recommendations]: https://developer.apple.com/documentation/packagedescription/product/library(name:type:targets:)
+
+{% include docs/swift-package-manager/how-to-enable-disable.md %}