Fix double -gg for git commit.

Version with node was displayed with `-gg957cca0`. The "g" was double.
3 jobs for master in 46 seconds (queued for 1 second)
Status Job ID Name Coverage
  Test
passed #524119433
test:py27

00:00:17

passed #524119432
test:py3

00:00:18

 
  Deploy
passed #524119435
github_push

00:00:28