docs(Diagrams): Update mermaid import mechanism (#1967)

content/en/content-management/diagrams.md

@@ -58,8 +58,8 @@ And then include this snippet at the bottom of the content template (**Note**: b
 
 ```go-html-template
 {{ if .Page.Store.Get "hasMermaid" }}
-  <script src="https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.min.js"></script>
-  <script>
+  <script type="module">
+    import mermaid from 'https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.esm.min.mjs';
     mermaid.initialize({ startOnLoad: true });
   </script>
 {{ end }}