Fixes typo hours= -> hour=.

Changelog

@@ -15,10 +15,11 @@
 
 See :ref:`whatsnew-2.5`.
 
-We decided to do things differently this time, considering the changelog
-is very long we're going to have separate documents for major version changes,
-called "what's new" documents.  Bugfix releases will still be located in the
-changelog.
+Since the changelog has gained considerable size, we decided to
+do things differently this time: by having separate "what's new"
+documents for major version changes.
+
+Bugfix releases will still be found in the changelog.
 
 .. _version-2.4.5:
 

FAQ

@@ -692,7 +692,7 @@ Or to schedule a periodic task at a specific time, use the
     from celery.task.schedules import crontab
     from celery.task import periodic_task
 
-    @periodic_task(run_every=crontab(hours=7, minute=30, day_of_week="mon"))
+    @periodic_task(run_every=crontab(hour=7, minute=30, day_of_week="mon"))
     def every_monday_morning():
         print("This is run every Monday morning at 7:30")