Change gitlab-runner user & workingdir

Config

```
gitlab-runner uninstall
```

gitlab-runner install --working-directory /opt/fsi-gitrunner --user admin

```
systemctl restart gitlab-runner
```

Check

ps axfh |grep -i gitlab

[root@fsi fsi-gitrunner]# ps axfh |grep -i gitlab
32608 ?        Ssl    0:00 /usr/bin/gitlab-runner run --working-directory /opt/fsi-gitrunner --config /etc/gitlab-runner/config.toml --service gitlab-runner --user admin
[root@fsi fsi-gitrunner]#

Authors:

Jochen Schnuerle