Issue #3485764 by japerry: Remove deprecated 'dash' from schema

config/schema/fallback_formatter.schema.yml

@@ -6,7 +6,7 @@ field.formatter.settings.fallback:
       type: sequence
       label: 'Formatters'
       sequence:
-        - type: mapping
+        type: mapping
         label: 'Formatter settings'
         mapping:
           status:

tests/src/Kernel/FallbackFormatterTestCase.php

@@ -3,9 +3,9 @@
 namespace Drupal\Tests\fallback_formatter\Kernel;
 
 use Drupal\Core\Render\Element;
+use Drupal\KernelTests\KernelTestBase;
 use Drupal\field\Entity\FieldConfig;
 use Drupal\field\Entity\FieldStorageConfig;
-use Drupal\KernelTests\KernelTestBase;
 use Drupal\node\Entity\Node;
 use Drupal\node\Entity\NodeType;
 use Drupal\node\NodeInterface;