PEP fixes

finishes work for #2318

InvenTree/plugin/builtin/integration/mixins.py

@@ -1,5 +1,4 @@
 """default shpping mixins for IntegrationMixins"""
-from django.conf import settings
 from django.conf.urls import url, include
 
 from plugin.urls import PLUGIN_BASE

InvenTree/templates/js/translated/plugin.js

@@ -23,4 +23,4 @@ function installPlugin() {
             showMessage(msg, {style: 'success', details: data.result, timeout: 30000});
         }
     });
-}
+}