Replace usage of oslo.log

Horizon doesn't rely on oslo.log and use the generic logging library
and the Django logger. Following that, this change replaces oslo.log
by the generic logging library, because the only requirement is to
provide access to the root logger instance which doesn't really require
oslo.log.

Change-Id: I2a4f029d5081bb27b30a6889b73f2ad655e74f42

designatedashboard/api/rest/passthrough.py

@@ -16,6 +16,7 @@
 from django.conf import settings
 from django.views import generic
 import functools
+import logging
 import requests
 from requests.exceptions import HTTPError
 
@@ -23,7 +24,6 @@ from horizon import exceptions
 from openstack_dashboard.api import base
 from openstack_dashboard.api.rest import urls
 from openstack_dashboard.api.rest import utils as rest_utils
-from oslo_log import log as logging
 
 LOG = logging.getLogger(__name__)
 

releasenotes/notes/remove-oslo-log-078df11995380f36.yaml

@@ -0,0 +1,4 @@
+---
+upgrade:
+  - |
+    The ``oslo.log`` library is no longer required.

requirements.txt

@@ -5,7 +5,6 @@
 # The order of packages is significant, because pip processes them in the order
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
-oslo.log>=3.36.0 # Apache-2.0
 pbr!=2.1.0,>=2.0.0 # Apache-2.0
 python-designateclient>=2.7.0 # Apache-2.0