Try to install the dependencies from other sources in the release
notes job, but ignore failures. This should allow projects with
unusual dependencies (most often oslosphnix) in their release notes
build to continue to work until we can simplify their dependency list.
Change-Id: I6b6d596eccb956f24a3ae3056a474ba347673c82
Signed-off-by: Doug Hellmann <doug@doughellmann.com>