How to update symfony with flex?

@kadin 

To update Symfony with Flex, follow these steps:

1. Update the Symfony Flex binary: composer global require --no-plugins --no-scripts symfony/flex ^1.0 --update-with-all-dependencies
2. Upgrade your project dependencies: composer require symfony/flex ^1.0 --dev This will update the Flex package and its dependencies in your project.
3. Update your Symfony packages: composer update symfony/* This will update all your Symfony packages to the latest versions.
4. Apply Flex recipes: composer require-env --dev This will check for recipe updates and apply any necessary changes to your project.
5. Clean up unused packages: composer sync-recipes --no-dev --force This will remove unused packages and update the recipes in your project.
6. Update the Flex configuration: composer recipes --exec This will update the Flex configuration based on the new recipes.
7. Update the Symfony binary: composer symfony:update This will update the Symfony binary to the latest version.

Note: Make sure to review the Symfony and Flex upgrade guides for any additional steps specific to your project's version.