add loader to project creation

src/views/project/Project_edit.vue

 <template>
   <div class="fourteen wide column">
+    <div
+      :class="{active: loading}"
+      class="ui inverted dimmer"
+    >
+      <div class="ui text loader">
+        Projet en cours de création. Vous allez être redirigé.
+      </div>
+    </div>
     <form id="form-project-edit" class="ui form">
       <h1>
         <span v-if="action === 'edit'"
@@ -206,6 +214,7 @@ export default {
 
   data() {
     return {
+      loading: false,
       action: "create",
       levelPermissions: [
         { name: "Utilisateur anonyme", value: "anonymous" },
@@ -376,6 +385,7 @@ export default {
       };
 
       if (this.action === "create" || this.action === "duplicate") {
+        this.loading = true;
         await axios
           .post(
             `${this.$store.state.configuration.VUE_APP_DJANGO_API_BASE}projects/`,
@@ -390,11 +400,13 @@ export default {
                 this.goBackNrefresh(response.data.slug);
               }
             }
+            this.loading = false;
           })
           .catch((error) => {
             if (error.response.data.title[0]) {
               this.errors.title.push(error.response.data.title[0]);
             }
+            this.loading = false;
             throw error;
           });
       } else if (this.action === "edit") {