I found out that we have some weird kind of repository sync problem.
AFAIK, we should be using this repository and it should contain everything we need to run RF builds/tests.
However some files are missing. I discovered this via Jenkins build which failed to fetch our zip configuration files (used for https testing & tomcat testing). Those files should be under build-resources sub-project but with the above repo, there are none.
I also came across this other repository which I had no idea it even exists, but it contains all files necessary.
With the above situation our usual 4.5 Jenkins jobs pass the builds since the other repository can be used. However release jobs all fail because there is no *.Final zip configuration files to be used in any repository. We need to somehow propagate those configs into our staging/release repos.
Side note: This must have been broken for quite a while, there were other issues preventing us from running https tests and tomcat tests (in automated manner). Those were fixed recently so this problem got revealed.