Add info when form is inactive to subscription form block

[MAILPOET-3896]

assets/js/src/post_editor_block/subscription_form/edit.jsx

@@ -26,7 +26,7 @@ function Edit({ attributes, setAttributes }) {
         <option value="" disabled selected>{window.locale.selectForm}</option>
         {allForms.map((form) => (
           <option value={form.id}>
-            {form.name}
+            {form.name + (form.status === 'disabled' ? ` (${window.locale.inactive})` : '')}
           </option>
         ))}
       </select>

lib/PostEditorBlocks/SubscriptionFormBlock.php

@@ -57,6 +57,7 @@ class SubscriptionFormBlock {
           selectForm: '<?php echo __('Select a MailPoet form', 'mailpoet') ?>',
           createForm: '<?php echo __('Create a new form', 'mailpoet') ?>',
           subscriptionForm: '<?php echo __('MailPoet Subscription Form', 'mailpoet') ?>',
+          inactive: '<?php echo __('inactive', 'mailpoet') ?>',
         };
       </script>
       <?php