[python] Use positional formatting in Python scripts

get-job-stats-from-mysql.py is not compatible with Python 2.6.x
beause it uses the format function without the positions included.

I also updated other calls to format without explicit positions.

Change-Id: I0eb17a5b0435e8e78a31124c8d9f3756583cd05a
Reviewed-on: http://gerrit.cloudera.org:8080/15075
Tested-by: Kudu Jenkins
Reviewed-by: Andrew Wong <awong@cloudera.com>
Reviewed-by: Bankim Bhavsar <bankim@cloudera.com>
5 files changed