title: Invalid type for path "security.firewalls.main.form_login". Expected array, but got string
body: <p>I am getting this error in my symfony project. My security.yml file code is below.</p>
  
  <pre><code># To get started with security, check out the documentation:
  # https://symfony.com/doc/current/security.html
  security:
      encoders:
          AppBundle\Emtity\User:
              algorithm: becrypt
  
      # https://symfony.com/doc/current/security.html#b-configuring-how-users-are-loaded
      providers:
          db_provider:
              entity:
                  class: AppBundle:User
                  property: username
  
      firewalls:
          # disables authentication for assets and the profiler, adapt it according to your needs
          dev:
              pattern: ^/(_(profiler|wdt)|css|images|js)/
              security: false
  
          main:
              anonymous: ~
              form_login:
                  login_path:login
                  check_path:login
  </code></pre>
  
  <p>You can also see my config.yml file whick look like be</p>
  
  <pre><code>imports:
      - { resource: parameters.yml }
      - { resource: security.yml }
      - { resource: services.yml }
  
  # Put parameters here that don't need to change on each machine where the app is deployed
  # https://symfony.com/doc/current/best_practices/configuration.html#application-related-configuration
  parameters:
      locale: en
  
  framework:
      #esi: ~
      #translator: { fallbacks: ['%locale%'] }
      secret: '%secret%'
      router:
          resource: '%kernel.project_dir%/app/config/routing.yml'
          strict_requirements: ~
      form: ~
      csrf_protection:
           enabled: true
      validation: { enable_annotations: true }
      #serializer: { enable_annotations: true }
      default_locale: '%locale%'
      trusted_hosts: ~
      session:
          # https://symfony.com/doc/current/reference/configuration/framework.html#handler-id
          handler_id: session.handler.native_file
          save_path: '%kernel.project_dir%/var/sessions/%kernel.environment%'
      fragments: ~
      http_method_override: true
      assets: ~
      php_errors:
          log: true
  
  # Twig Configuration
  twig:
      debug: '%kernel.debug%'
      strict_variables: '%kernel.debug%'
  
  # Doctrine Configuration
  doctrine:
      dbal:
          driver: pdo_mysql
          host: '%database_host%'
          port: '%database_port%'
          dbname: '%database_name%'
          user: '%database_user%'
          password: '%database_password%'
          charset: UTF8
          # if using pdo_sqlite as your database driver:
          #   1. add the path in parameters.yml
          #     e.g. database_path: '%kernel.project_dir%/var/data/data.sqlite'
          #   2. Uncomment database_path in parameters.yml.dist
          #   3. Uncomment next line:
          #path: '%database_path%'
  
      orm:
          auto_generate_proxy_classes: '%kernel.debug%'
          naming_strategy: doctrine.orm.naming_strategy.underscore
          auto_mapping: true
  
  # Swiftmailer Configuration
  swiftmailer:
      transport: '%mailer_transport%'
      host: '%mailer_host%'
      username: '%mailer_user%'
      password: '%mailer_password%'
      spool: { type: memory }
  </code></pre>
  
  <p>Please check above code i don't know which thing are missing in my code so please help me if anyone have got any solution.</p>
  
  <p>I want to try login process in symfony using the security.yml file.</p>