This speeds up CI pipelines by skipping the fetch job, which takes ~ 8 minutes
when there is nothing to fetch (bitbake parsing is slow...).

If/when needed, the fetch job can be run manually, to oupdate the cached source
mirror.

TODO: Add support for periodically scheduling run with fetch job running
automatically.

Signed-off-by: Esben Haabendal <esben.haabendal@huawei.com>