Remove the upload_letters permission

Every service has it now, and we haven’t had any services ask to toggle
it off again.

app/main/views/service_settings.py

@@ -67,7 +67,6 @@ from app.utils import (
 PLATFORM_ADMIN_SERVICE_PERMISSIONS = OrderedDict([
     ('inbound_sms', {'title': 'Receive inbound SMS', 'requires': 'sms', 'endpoint': '.service_set_inbound_number'}),
     ('email_auth', {'title': 'Email authentication'}),
-    ('upload_letters', {'title': 'Uploading letters', 'requires': 'letter'}),
     ('international_letters', {'title': 'Send international letters', 'requires': 'letter'}),
     ('broadcast', {'title': 'Send cell broadcasts'}),
 ])

app/main/views/uploads.py

@@ -341,7 +341,7 @@ def view_letter_upload_as_preview(service_id, file_id):
 @main.route("/services/<uuid:service_id>/upload-letter/send/<uuid:file_id>", methods=['POST'])
 @user_has_permissions('send_messages', restrict_admin_usage=True)
 def send_uploaded_letter(service_id, file_id):
-    if not (current_service.has_permission('letter') and current_service.has_permission('upload_letters')):
+    if not current_service.has_permission('letter'):
         abort(403)
 
     metadata = get_letter_metadata(service_id, file_id)