t() calls should be avoided in classes, use dependency injection and $this->t() instead

FILE: /var/www/html/drupal-contrib/modules/contrib/commerce_omnikassa/src/PluginForm/OffsiteRedirect/RedirectCheckoutForm.php
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FOUND 0 ERRORS AND 3 WARNINGS AFFECTING 3 LINES
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55 | WARNING | t() calls should be avoided in classes, use \Drupal\Core\StringTranslation\StringTranslationTrait and $this->t() instead
56 | WARNING | t() calls should be avoided in classes, use \Drupal\Core\StringTranslation\StringTranslationTrait and $this->t() instead
158 | WARNING | Unused variable $key.
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