Resolve "code of conduct confirmation needs token, otherwise 403."

What does this mr do?

See #705 (closed) for a description and screencast.

Actions taken to fix bug

Adds CSRF to fetch.

Before

After

Works as intended.

Does this MR meet the acceptance criteria?

• I adhere to the style guide.

Closes #705 (closed)

src/main/resources/templates/code_of_conduct.html

@@ -67,6 +67,9 @@
                 }
                 fetch("/profile/code-of-conduct/update", {
                     method: "POST",
+                    headers: {
+                        "X-CSRF-TOKEN": csrfToken,
+                    },
                 });
             });
         </script>