Add timestamps to pypi mirror jobs.

* modules/openstack_project/files/jenkins_job_builder/config/mirror.yaml:
A wrapper section is defined for the jobs in mirror.yaml so the default
timestamps addition is not included. Add timestamps to the wrapper
overrides in mirror.yaml.

Change-Id: Iacc47cf3a92489979cc76621d3f804be76d4688f
Reviewed-on: https://review.openstack.org/28366
Approved: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Tested-by: Jenkins
Bump mirror job timeout to 60 minutes.

Change-Id: I20ddac74f7e2dd3086cf7574751db4eade7715e9
Reviewed-on: https://review.openstack.org/28368
Approved: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Tested-by: Jenkins