Drop a no longer relevant sentence on gitlab-ci.yml

Signed-off-by: Andrej Shadura <andrew.shadura@collabora.co.uk>

content/guides/gitlab-based_packaging_workflow.md

@@ -33,10 +33,6 @@ following conventions:
   tarballs stored on Git-LFS via
   [pristine-lfs](https://gitlab.apertis.org/infrastructure/pristine-lfs)
 
-In addition, all the packaging repositories contains a
-`debian/apertis/gitlab-ci.yml` file to enable the CI pipeline which generates
-source packages and uploads them to OBS.
-
 # Development environment
 
 All the instructions below assume an Apertis development enviroment: either