fix(admin): keep the membership refuse button enabled without a reason (#1277)

Closes datagouv/data.gouv.fr#2108
Requires opendatateam/udata#4014

Co-authored-by: Conciergerie AI <contact@conciergerie.dev>

Author: nicolaskempf57

components/AdminMembershipRequest/AdminMembershipRequest.vue

@@ -184,7 +184,7 @@
               <BrandedButton
                 type="submit"
                 color="primary"
-                :disabled="loading || !refuseComment"
+                :disabled="loading"
                 :form="refuseFormId"
               >
                 {{ t("Refuser la demande") }}