Fix issues reported by PHPStan

Working on it.

Fixed the PHPStan issues of returnValue() function.
Could not figure out how to remove the first error of Plugin definitions alterations. However found a source where similar issue is stated.
Plugin Definition cannot be altered. Issue on Github.
Someone may look into it and proceed further

This should be done for the 2.1.x branch. I know the default was 2.0.x but I don't have the correct right to change. I'll ask the maintainer to change this.

Only one error remains

 ------ ----------------------------------------- 
  Line   src/Plugin/FieldWidgetPluginManager.php  
 ------ ----------------------------------------- 
  14     Plugin definitions cannot be altered.    
 ------ ----------------------------------------- 
 [ERROR] Found 1 error      

I saw another issue with probably the solution https://www.drupal.org/project/message_notify/issues/3414123 📌 Issues reported by phpStan Active

Checking if it solves the issue.

No more phpstan errors.

Hi @sayan_k_dutta,

I have checked the pipeline and reran the phpstan job. Confirmed the job succeeded.

Will now move this to RTBC.

Thanks,
J//ake

New error appeared

 ------ ----------------------------------------------------------------- 
  Line   src/Form/SettingsForm.php                                        
 ------ ----------------------------------------------------------------- 
  266    Call to deprecated method clearCachedDefinitions() of interface  
         Drupal\Core\Asset\LibraryDiscoveryInterface:                     
         in drupal:11.1.0 and is removed from drupal:12.0.0. Use          
         LibraryDiscoveryCollector::clear() instead.                      
 ------ ----------------------------------------------------------------- 

Change notice: LibraryDiscovery class is deprecated →
📌 Deprecate LibraryDiscovery and use LibraryDiscoveryCollector instead Fixed
https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Asset%21L...

@todo Use the deprecated method helper.
DeprecationHelper helps modules support multiple versions of core →

Could also autowire the drush services.