Issue #3274819: Fix Notice: Undefined index: import in EmailBuilderManager->getImportInfo()

Closes #3274819

src/Processor/EmailBuilderManager.php

@@ -100,7 +100,7 @@ class EmailBuilderManager extends DefaultPluginManager implements EmailBuilderMa
     $state_all = $this->keyValue->get('import', []);
 
     foreach ($this->getDefinitions() as $id => $definition) {
-      if ($definition['import']) {
+      if (isset($definition['import']) && $definition['import']) {
         $state = $state_all[$id] ?? self::IMPORT_READY;
 
         $info[$id] = [