Remove encoding header

Fixes #2996

InvenTree/build/api.py

@@ -2,9 +2,6 @@
 JSON API for the Build app
 """
 
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.urls import include, re_path
 
 from rest_framework import filters, generics

InvenTree/build/models.py

@@ -2,8 +2,6 @@
 Build database model definitions
 """
 
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
 import decimal
 
 import os

InvenTree/build/serializers.py

@@ -2,9 +2,6 @@
 JSON serializers for Build API
 """
 
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db import transaction
 from django.core.exceptions import ValidationError as DjangoValidationError
 from django.utils.translation import gettext_lazy as _

InvenTree/build/views.py

@@ -2,9 +2,6 @@
 Django views for interacting with Build objects
 """
 
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.utils.translation import gettext_lazy as _
 from django.views.generic import DetailView, ListView