Reenable apt repo path in between shipping dists

We have to do this in order to actually update the apt repo with every
distribution. Otherwise rake things we've already done it.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Merge pull request #251 from MosesMendoza/maint/master/correct_pe_ship

Reenable apt repo path in between shipping dists