docs(kicker): add job prefix attribute

{{cookiecutter.project_slug}}/kicker.json

@@ -5,6 +5,7 @@
   "template_path": "templates/gitlab-ci-{{cookiecutter.project_slug}}.yml",
   "kind": "build",
   "prefix": "{{cookiecutter.template_prefix}}",
+  "job_prefix": "{{cookiecutter.template_prefix}}",
   "is_component": true,
   "variables": [
     {