Fix MySQL build

src/TestSuite/Fixture/FixtureManager.php

@@ -344,6 +344,13 @@ class FixtureManager
         }
         $truncate = function ($db, $fixtures) {
             $configName = $db->configName();
+
+            foreach ($fixtures as $name => $fixture) {
+                if ($this->isFixtureSetup($configName, $fixture)) {
+                    $fixture->dropConstraints($db);
+                }
+            }
+
             foreach ($fixtures as $fixture) {
                 if ($this->isFixtureSetup($configName, $fixture)) {
                     $fixture->truncate($db);

tests/TestCase/TestSuite/FixtureManagerTest.php

@@ -107,7 +107,6 @@ class FixtureManagerTest extends TestCase
         $this->assertEquals($expectedConstraint, $schema->constraint('tag_id_fk'));
 
         $this->manager->unload($test);
-        $this->manager->shutDown($test);
     }
 
     /**