fix: only use destination's pickup values

assets/controllers/form_partial_controller.js

@@ -0,0 +1,35 @@
+import { Controller } from '@hotwired/stimulus'
+import { useFetch } from '../mixins/use_fetch'
+
+export default class extends Controller {
+
+    static targets = [ 'form', 'container', 'spinner' ]
+    static values = { url: String, loading: Boolean }
+
+    connect() {
+        useFetch(this)
+    }
+
+    update() {
+        this.loadingValue = true
+        const formData = new FormData(this.formTarget)
+        fetch(this.urlValue, { method: 'POST', body: formData })
+            .then(this.checkStatus)
+            .then(this.parseHTML)
+            .then(response => {
+                this.containerTarget.innerHTML = response
+            })
+            .catch(error => {
+            })
+            .finally(() => {
+                this.loadingValue = false
+            })
+
+    }
+
+    loadingValueChanged(loading) {
+        if (this.hasSpinnerTarget) {
+            this.spinnerTarget.classList.toggle('hidden', false === loading)
+        }
+    }
+}