update terms to clarify they prevail over gitlab quotes or invoices

source/_includes/subscription_terms.html

@@ -5,6 +5,13 @@
 </p>
 <ol>
+  <li>
+    <strong>General terms</strong>
+    <p>
+      If there is a conflict between the terms of this Agreement and any text on the GitLab quote or the GitLab invoice, the terms of this Agreement prevail over those in either the quote or the invoice.
+    </p>
+  </li>
+
   <li>
     <strong>Services</strong>
     <p>