Add an example of conf interval in the guide

4 jobs for theo-conf-inter in 19 minutes and 4 seconds (queued for 5 seconds)
Status Name Job ID Coverage
  Build
passed build_linux_27 #127221
docker

00:08:21

58.0%
passed build_linux_36 #127222
docker

00:08:22

58.0%
passed build_macosx_27 #127223
macosx

00:19:04

58.0%
passed build_macosx_36 #127224
macosx

00:18:36

58.0%