NXCM-5283: Explicitly relocate obr bundle

As ObrProxy actually does that, it relocates all
the cached bundles to "/bundles" folder. Still, it relied
on a fact that post-retrieval the item associated request
is still tied to original one (only referenced).

After NEXUS-5511 fix, this is not the case anymore, so
after the request.popRequestPath an explicit setting
is needed to be done too.