align new mathjax dashboards to PR 6096

Author: archmoj

devtools/test_dashboard/index-mathjax3.html

@@ -23,7 +23,7 @@
   <div id="snapshot"></div>
 
   <script src="../../node_modules/mathjax-v3/es5/tex-svg.js"></script>
-  <script charset="utf-8" id="source"  type="module">import "../../build/plotly.js"</script>
+  <script charset="utf-8" id="source" src="../../build/plotly.js" type="module"></script>
   <script charset="utf-8" src="../../build/test_dashboard-bundle.js"></script>
 </body>
 </html>

devtools/test_dashboard/index-mathjax3chtml.html

@@ -61,7 +61,7 @@
   </script>
   <script src="../../node_modules/mathjax-v3/es5/tex-chtml.js"></script>
 
-  <script charset="utf-8" id="source"  type="module">import "../../build/plotly.js"</script>
+  <script charset="utf-8" id="source" src="../../build/plotly.js" type="module"></script>
   <script charset="utf-8" src="../../build/test_dashboard-bundle.js"></script>
 </body>
 </html>