Before building jw-pkg from source, make pkg-install-release-deps is called without refreshing the package manager before. Fix that by calling make -C jw-pkg pkg-manager-refresh.
Note that it's called again later. Leaving that in because the second step doesn't hurt, and the first steppe might get scrapped entirely at some point.
Signed-off-by: Jan Lindemann <jan@janware.com>