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

Problem/Motivation

FOUND 0 ERRORS AND 12 WARNINGS AFFECTING 12 LINES
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 836 | WARNING | t() calls should be avoided in classes, use
     |         | \Drupal\Core\StringTranslation\StringTranslationTrait
     |         | and $this->t() instead
 839 | WARNING | t() calls should be avoided in classes, use
     |         | \Drupal\Core\StringTranslation\StringTranslationTrait
     |         | and $this->t() instead
 842 | WARNING | t() calls should be avoided in classes, use
     |         | \Drupal\Core\StringTranslation\StringTranslationTrait
     |         | and $this->t() instead
 845 | WARNING | t() calls should be avoided in classes, use
     |         | \Drupal\Core\StringTranslation\StringTranslationTrait

Steps to reproduce

Run phpcs.

Proposed resolution

use $this->t() instead of t().