Oops, fix locale form with Turbo pageloads

Before this change, this would only work on the first pageload, and
fail after doing a Turbo page navigation. Now, it works all the time!

app/javascript/application.js

@@ -1,5 +1,6 @@
 import "@hotwired/turbo-rails";
 
-document.getElementById("locale").addEventListener("change", function () {
+document.addEventListener("change", (e) => {
+	if (!e.target.matches("#locale")) return;
 	document.getElementById("locale-form").submit();
 });