t() calls should be avoided in classes

FILE: ...web/modules/contrib/maintenance200/src/Form/Maintenance200SettingsForm.php
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FOUND 0 ERRORS AND 3 WARNINGS AFFECTING 3 LINES
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39 | WARNING | t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait and
| | $this->t() instead
44 | WARNING | t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait and
| | $this->t() instead
48 | WARNING | #description values usually have to run through t() for
| | translation