chore: Add extra explanation message for Policy Redirect URL

Author: smessie

app/templates/index.hbs

@@ -179,6 +179,7 @@
 
           <hr>
 
+          <h6 class="card-subtitle mb-2 text-muted">Fill in the URL to which the user should be sent after submitting the form.</h6>
           <div class="mb-3 row">
             <label for="policy-redirect-url-{{this.model.form.uuid}}" id="label-policy-redirect-url-{{this.model.form.uuid}}"
                    class="col-sm-3 col-form-label">Policy Redirect URL</label>