set 'restricted_html' as default text format

src/Form/ModuleConfigurationForm.php

@@ -76,7 +76,7 @@ class ModuleConfigurationForm extends ConfigFormBase {
       '#type' => 'text_format',
       '#title' => $this->t('Footer Text'),
       '#description' => $this->t('This content will be displayed in the footer below the contact info. It can contain links or other pertinent information. This is a good place for your ADA statement.'),
-      '#format' => 'basic_html',
+      '#format' => 'restricted_html',
       '#default_value' => $config->get('footer_text.value'),
     );