replace deprecated constant REQUIREMENT_ERROR by RequirementSeverity::Error

💬 Description

replace deprecated constant REQUIREMENT_ERROR by RequirementSeverity::Error

🎟️ Issue(s)

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  Line   src/Controller/OverviewController.php                           
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  128    Fetching deprecated class constant REQUIREMENT_ERROR of class   
         Drupal\system\SystemManager:                                    
         in drupal:11.2.0 and is removed from drupal:12.0.0. Use         
          \Drupal\Core\Extension\Requirement\RequirementSeverity::Error  
         instead.                                                        
         🪪 classConstant.deprecated                                     
  142    Fetching deprecated class constant REQUIREMENT_ERROR of class   
         Drupal\system\SystemManager:                                    
         in drupal:11.2.0 and is removed from drupal:12.0.0. Use         
          \Drupal\Core\Extension\Requirement\RequirementSeverity::Error  
         instead.                                                        
         🪪 classConstant.deprecated                                     
  155    Fetching deprecated class constant REQUIREMENT_ERROR of class   
         Drupal\system\SystemManager:                                    
         in drupal:11.2.0 and is removed from drupal:12.0.0. Use         
          \Drupal\Core\Extension\Requirement\RequirementSeverity::Error  
         instead.                                                        
         🪪 classConstant.deprecated                                     
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• Update the "Unreleased" section of the CHANGELOG.md with chan