PrintTestPage: fix indentation

Not sure this is really causing any problems, but I've seen:

Traceback:
File ".../troubleshoot/__init__.py", line 360, in run
    exec ("from .%s import %s" % (module, module))
File "<string>", line 1, in <module>
File ".../troubleshoot/PrintTestPage.py", line 497

which (maybe only the last line is relevant) points to this line.

Author: jpopelka

troubleshoot/PrintTestPage.py

@@ -494,7 +494,7 @@ def get_notifications (self):
         test_jobs = self.persistent_answers.get('test_page_job_id', [])
         for event in notifications['events']:
             seq = event['notify-sequence-number']
-	    self.sub_seq = seq
+            self.sub_seq = seq
 
             job = event['notify-job-id']