TEMP: Remove ROS' octomap after 'rosdep install'

[rhaschke]

Quick, temporary solution for #2851 (comment).

[henningkayser]

I pulled this into #2851 for now to complete the CI fixes, even though this should really only be a short-term solution.
If possible, we should not prevent users to have the ROS package installed. I'm thinking about solving this by setting a version filter in the find_package call. Unfortunately, we can not declare the liboctomap-dev dependency in the package.xml, but at least we know that it must be available since it must be provided along with fcl.

I'm continuing to track this in #2846

[rhaschke]

At least we know that it (octomap) must be available since it must be provided along with fcl.

That's true for moveit_core, but not for geometric_shapes!

I explicitly filed a new PR for this change to not mangle it as part of #2851. This will allow to revert the change more easily in the future.