LambdaNotUsedImportFixer - add heredoc test

Author: SpacePossum

tests/Fixer/FunctionNotation/LambdaNotUsedImportFixerTest.php

@@ -196,6 +196,19 @@ public function provideDoNotFixCases()
             'interpolation 3' => [
                 '<?php $foo = function() use ($world) { echo "hello ${world}"; };',
             ],
+            'heredoc' => [
+                '<?php
+$b = 123;
+$foo = function() use ($b) {
+    echo
+<<<"TEST"
+Foo $b
+TEST;
+};
+
+$foo();
+',
+            ],
         ];
     }
 }