Fix: error when flatpickr instance not yet set (#238)

In some situations like when navigating to a page with vue-router / inertiajs that is having this component you will see `Uncaught (in promise) TypeError: Cannot read property 'emitsOptions' of null`

src/component.js

@@ -174,6 +174,10 @@ export default {
     config: {
       deep: true,
       handler(newConfig) {
+        if (!this.fp) {
+          return;
+        }
+
         let safeConfig = cloneObject(newConfig);
         // Workaround: Don't pass hooks to configs again otherwise
         // previously registered hooks will stop working