[scripts] Don't update _ci environment on buildout reruns

4 jobs for 1.7.x in 49 minutes and 11 seconds (queued for 3 seconds)
Status Name Job ID Coverage
  Build
passed build_linux_36 #153297
docker-build

00:30:29

73.0%
passed build_macosx_36 #153291
macosx

00:18:08

73.0%
failed build_linux_36 #153290
docker-build

00:34:20

73.0%
 
  Deploy
passed deploy_beta #153292
deployer

00:00:34