Updated email confirmation flow so confirmation is done via POST

To avoid non-user GET requests (Such as those from email scanners)
auto-triggering the confirm submission. Made auto-submit the form via
JavaScript in this extra added step with user-link backup to keep
existing user flow experience.

Closes #3797

resources/js/components/auto-submit.js

@@ -0,0 +1,12 @@
+
+class AutoSubmit {
+
+    setup() {
+        this.form = this.$el;
+
+        this.form.submit();
+    }
+
+}
+
+export default AutoSubmit;