gitlab-runner does not find jobs from included files
### Summary
Running jobs from included CI configuration files via `gitlab-runner exec docker myjob` does not work.
### Steps to reproduce
See Example Project.
### Example Project
See this simple [Example](https://gitlab.com/jonnius/gitlabrunnerfail/pipelines/117898420). Both jobs run smoothly on gitlab CI. But only `test-job-1` runs with `gitlab-runner`:
```
$ gitlab-runner exec docker test-job-1
[…]
$ echo Job 1
Job 1
$ gitlab-runner exec docker test-job-2
[…]
FATAL: no job named "test-job-2"
```
### What is the current *bug* behavior?
Running included job via `gitlab-runner` leads to `FATAL: no job named "myjob"`.
### What is the expected *correct* behavior?
Running included job via `gitlab-runner` runs the job as it does for jobs that live in `.gitlab-ci.yml` directly.
### Relevant logs and/or screenshots
See Example Project.
### Output of checks
None
#### Results of GitLab environment info
```
$ gitlab-runner -v
Version: 12.7.1
Git revision: 003fe500
Git branch: 12-7-stable
GO version: go1.13.5
Built: 2020-01-23T09:08:54+0000
OS/Arch: linux/amd64
```
#### Results of GitLab application Check
None
### Possible fixes
No idea.
issue