Remove html_last_updated_fmt

openstackdocstheme handles this itself and parses git date, no need
to set it anymore.

Change-Id: I9a832d7dbe48dae569afee252f63ec2cf6f42df0

doc/source/conf.py

@@ -115,13 +115,6 @@ html_theme = 'openstackdocs'
 # pixels large.
 #html_favicon = None
 
-# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
-# using the given strftime format.
-git_cmd = ["git", "log", "--pretty=format:'%ad, commit %h'", "--date=local",
-           "-n1"]
-html_last_updated_fmt = subprocess.Popen(
-    git_cmd, stdout=subprocess.PIPE).communicate()[0].decode('utf-8')
-
 # If true, SmartyPants will be used to convert quotes and dashes to
 # typographically correct entities.
 #html_use_smartypants = True