[FIX] web: correct append of the autocomplete widget in the viewmanager

Adapt rev 4a3e5df93a and rev e1cde4d038 to the current webclient
structure. Without this patch, autocomplete widget is completely broken
with multiple viewmanager.

addons/web/static/src/js/view_form.js

@@ -3746,8 +3746,8 @@ instance.web.form.FieldMany2One = instance.web.form.AbstractField.extend(instanc
             minLength: 0,
             delay: 250,
         });
-        var appendTo = this.$el.parents('.oe_view_manager_body, .modal-dialog').last();
-        if (appendTo.length === 0){
+        var appendTo = this.$input.parents('.oe-view-manager-content, .modal-dialog').last();
+        if (appendTo.length === 0) {
             appendTo = '.oe_application > *';
         }
         this.$input.autocomplete({