Revert "Configure jessie repos in LTS mode during Docker build (#6887)" (#6889)
Revert "Configure jessie repos in LTS mode during Docker build (#6887)" (#6889)

This reverts commit a27bd28b39e5312ef77d5767a989fc4661e179fb.
stweil/letsencrypt,lmcro/letsencrypt,stweil/letsencrypt,lmcro/letsencrypt,letsencrypt/letsencrypt,letsencrypt/letsencrypt