fix(next): url form element for Next.js site form

Fixes #614

Co-authored-by: John Albin Wilkins <virtually.johnalbin@gmail.com>

Author: mglaman

modules/next/src/Form/NextSiteForm.php

@@ -38,7 +38,7 @@ public function form(array $form, FormStateInterface $form_state) {
     ];
 
     $form['base_url'] = [
-      '#type' => 'textfield',
+      '#type' => 'url',
       '#title' => $this->t('Base URL'),
       '#description' => $this->t('Enter the base URL for the Next.js site. Example: <em>https://example.com</em>.'),
       '#default_value' => $entity->getBaseUrl(),
@@ -60,7 +60,7 @@ public function form(array $form, FormStateInterface $form_state) {
     ];
 
     $form['preview']['preview_url'] = [
-      '#type' => 'textfield',
+      '#type' => 'url',
       '#title' => $this->t('Preview URL'),
       '#description' => $this->t('Enter the preview URL. Example: <em>https://example.com/api/preview</em>.'),
       '#default_value' => $entity->getPreviewUrl(),
@@ -83,7 +83,7 @@ public function form(array $form, FormStateInterface $form_state) {
     ];
 
     $form['revalidation']['revalidate_url'] = [
-      '#type' => 'textfield',
+      '#type' => 'url',
       '#title' => $this->t('Revalidate URL'),
       '#description' => $this->t('Enter the revalidate URL. Example: <em>https://example.com/api/revalidate</em>.'),
       '#default_value' => $entity->getRevalidateUrl(),