Replace broken links in how-shipkit-works.md
## How Shipkit works?
Want to find out how Shipkit works?
-- see also [getting started guide](doc/getting-started.md)
-- or the entire [documentation index](README.md#documentation)
+- see also [getting started guide](/docs/getting-started.md)
+- or the entire [documentation index](/README.md#documentation)
### Version bumps
