⏫ Forwardport of magento/magento2#12308 to 2.3-develop branch

Applied pull request patch https://github.com/magento/magento2/pull/12308.patch (created by @RomaKis) based on commit(s):
  1. 24eee64
  2. ec33cc5

Fixed GitHub Issues in 2.3-develop branch:
  - magento/magento2#12261: Order confirmation email contains non functioning links (reported by @bondimedical3)

Author: magento-engcom-team

app/design/frontend/Magento/luma/Magento_Email/email/footer.html

@@ -17,8 +17,16 @@
                         <table>
                             <tr>
                                 <td>
-                                    <p><a href="#">{{trans "About Us"}}</a></p>
-                                    <p><a href="#">{{trans "Customer Service"}}</a></p>
+                                    {{depend url_about_us}}
+                                    <p>
+                                        {{trans '<a href=%url_about_us>About Us</a>' url_about_us=$url_about_us |raw}}
+                                    </p>
+                                    {{/depend}}
+                                    {{depend url_customer_service}}
+                                    <p>
+                                        {{trans '<a href=url_customer_service>Customer Service</a>' url_customer_service=$url_customer_service |raw}}
+                                    </p>
+                                    {{/depend}}
                                 </td>
                                 <td>
                                     {{depend store_phone}}