Override view permissions for plugin list API

- It is necessary for *any* logged in user to view this endpoint
- This is how the user determines which plugins are available (e.g. for label printing!)

InvenTree/plugin/api.py

@@ -9,6 +9,7 @@ from django.conf.urls import url, include
 
 from rest_framework import generics
 from rest_framework import status
+from rest_framework import permissions
 from rest_framework.response import Response
 
 from common.api import GlobalSettingsPermissions
@@ -22,6 +23,11 @@ class PluginList(generics.ListAPIView):
     - GET: Return a list of all PluginConfig objects
     """
 
+    # Allow any logged in user to read this endpoint
+    # This is necessary to allow certain functionality,
+    # e.g. determining which label printing plugins are available 
+    permission_classes = [permissions.IsAuthenticated]
+
     serializer_class = PluginSerializers.PluginConfigSerializer
     queryset = PluginConfig.objects.all()