244: Apparently, array_map() does not handle keyed arrays

tests/src/Unit/process/TransposeTest.php

@@ -50,8 +50,8 @@ class TransposeTest extends MigrateProcessTestCase {
       ],
       'image files and alt text' => [
         'input' => [
-          'src' => ['2.png', '3.png', '5.png', '7.png'],
-          'alt' => ['two', 'three', 'five', 'seven'],
+          ['2.png', '3.png', '5.png', '7.png'],
+          ['two', 'three', 'five', 'seven'],
         ],
         'expected_output' => [
           ['2.png', 'two'],