Drupal 9 readiness

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  Line   entity_extra_field.module
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  105    PHPDoc tag @param has invalid value ($build
         An array of elements to attach the extra field.): Unexpected token
         "$build", expected type at offset 106
  105    PHPDoc tag @param has invalid value ($type
         The display type, (e.g. view, form).): Unexpected token "$type",
         expected type at offset 48
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  Line   modules/entity_extra_field_ui/src/Plugin/Derivative/MenuLinksAction.php
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  37     Unsafe usage of new static().
         💡 Consider making the class or the constructor final.
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  Line   modules/entity_extra_field_ui/src/Plugin/Derivative/MenuLinksTask.php
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  37     Unsafe usage of new static().
         💡 Consider making the class or the constructor final.
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  Line   src/Controller/EntityExtraFieldListBuilder.php
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  60     Unsafe usage of new static().
         💡 Consider making the class or the constructor final.
  84     Call to an undefined method
         Drupal\Core\Entity\EntityInterface::getFieldTypeLabel().
  85     Call to an undefined method
         Drupal\Core\Entity\EntityInterface::getDisplayType().
  137    Method
         Drupal\entity_extra_field\Controller\EntityExtraFieldListBuilder::get
         BaseEntityBundleType() should return
         bool|Drupal\Core\Config\Entity\ConfigEntityInterface but returns
         null.
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  Line   src/Entity/EntityExtraField.php
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  326    Method Drupal\entity_extra_field\Entity\EntityExtraField::exists()
         should return int but returns bool.
  360    If condition is always true.
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  Line   src/Entity/EntityExtraFieldInterface.php
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  156    PHPDoc tag @param has invalid value ($type
         The type of attachment (library, drupalSettings, etc)): Unexpected
         token "$type", expected type at offset 50
  170    PHPDoc tag @param has invalid value ($name
         The entity machine name.): Unexpected token "$name", expected type at
         offset 60
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  Line   src/ExtraFieldTypePluginBase.php
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  69     PHPDoc tag @param has invalid value ($plugin_definition
         The plugin definition.): Unexpected token "$plugin_definition",
         expected type at offset 180
  69     PHPDoc tag @param has invalid value ($plugin_id
         The plugin identifier.): Unexpected token "$plugin_id", expected type
         at offset 127
  96     Unsafe usage of new static().
         💡 Consider making the class or the constructor final.
  268    PHPDoc tag @param has invalid value ($text
         The text that contains the token.): Unexpected token "$text",
         expected type at offset 57
  289    PHPDoc tag @param has invalid value ($entity_bundle
         The entity bundle name.): Unexpected token "$entity_bundle", expected
         type at offset 113
  289    PHPDoc tag @param has invalid value ($entity_type_id
         The entity type identifier.): Unexpected token "$entity_type_id",
         expected type at offset 50
  342    PHPDoc tag @param has invalid value ($entity_bundle
         The entity bundle name.): Unexpected token "$entity_bundle", expected
         type at offset 123
  342    PHPDoc tag @param has invalid value ($entity_type_id
         The entity type identifier.): Unexpected token "$entity_type_id",
         expected type at offset 60
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  Line   src/Form/EntityExtraFieldForm.php
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  82     Unsafe usage of new static().
         💡 Consider making the class or the constructor final.
  318    PHPDoc tag @param has invalid value ($plugin_id
         The field type plugin identifier.): Unexpected token "$plugin_id",
         expected type at offset 67
  356    Call to an undefined method
         Drupal\Component\Plugin\PluginManagerInterface::getDefinitionsForCont
         exts().
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  Line   src/Plugin/ExtraFieldType/ExtraFieldBlockPlugin.php
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  76     PHPDoc tag @param has invalid value ($plugin_definition
         The plugin definition.): Unexpected token "$plugin_definition",
         expected type at offset 183
  76     PHPDoc tag @param has invalid value ($plugin_id
         The plugin identifier.): Unexpected token "$plugin_id", expected type
         at offset 130
  99     Property
         Drupal\entity_extra_field\Plugin\ExtraFieldType\ExtraFieldBlockPlugin
         ::$blockManager (Drupal\Core\Entity\EntityTypeManagerInterface) does
         not accept Drupal\Core\Block\BlockManagerInterface.
  113    Unsafe usage of new static().
         💡 Consider making the class or the constructor final.
  316    Result of || is always true.
  319    Unreachable statement - code above always terminates.
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  Line   src/Plugin/ExtraFieldType/ExtraFieldViewsPlugin.php
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  57     Variable $instance in PHPDoc tag @var does not match assigned
         variable $view.
  102    Variable $view in PHPDoc tag @var does not exist.
  103    Cannot call method getDependencies() on
         Drupal\Core\Entity\EntityInterface|true.
  263    PHPDoc tag @param has invalid value ($view_name
         The view name.): Unexpected token "$view_name", expected type at
         offset 46
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  Line   templates/entity_extra_field.theme
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  13     Function template_preprocess_entity_extra_field not found while
         trying to analyse it - autoloading is probably not configured
         properly.
  22     Function entity_extra_field_class_string not found.
  43     Function entity_extra_field_class_string not found while trying to
         analyse it - autoloading is probably not configured properly.
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 [ERROR] Found 36 errors