t() calls should be avoided in classes

$ phpcs --standard=Drupalpractice --extensions=php,module,inc,install,test,profile,theme,css,info,txt,md,yml string/
Xdebug: [Step Debug] Time-out connecting to debugging client, waited: 200 ms. Tried: localhost:9000 (through xdebug.client_host/xdebug.client_port) :-(

FILE: C:\Users\SI-001\Downloads\string\modules\string_tmgmt\src\Plugin\tmgmt\Source\StringSource.php
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FOUND 0 ERRORS AND 1 WARNING AFFECTING 1 LINE
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23 | WARNING | t() calls should be avoided in classes, use \Drupal\Core\StringTranslation\StringTranslationTrait and $this->t() instead
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FILE: C:\Users\SI-001\Downloads\string\src\Form\ExportForm.php
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90 | WARNING | t() calls should be avoided in classes, use \Drupal\Core\StringTranslation\StringTranslationTrait and $this->t() instead
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