No tests will block the configuration step

[kazuki0824]

Problems

If CATKIN_ENABLE_TESTING is set to OFF, configuration fails in noetic.

catlkin b openrtm_tools --summarize --cmake-args -DCATKIN_ENABLE_TESTING=OFF

Starting  >>> openrtm_tools                                                                                                                                                                                                                                                      
_________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Errors     << openrtm_tools:cmake /root/hlab-nxo-setup/overlay_ws/logs/openrtm_tools/build.cmake.002.log                                                                                                                                                                         
CMake Error at /opt/ros/noetic/share/catkin/cmake/test/tests.cmake:18 (message):
  () is not available when tests are not enabled.  The CMake code should only
  use it inside a conditional block which checks that testing is enabled:

  if(CATKIN_ENABLE_TESTING)

    (...)

  endif()

Call Stack (most recent call first):
  CMakeLists.txt:143 (add_rostest)


cd /root/hlab-nxo-setup/overlay_ws/build/openrtm_tools; catkin build --get-env openrtm_tools | catkin env -si  /usr/bin/cmake /root/hlab-nxo-setup/overlay_ws/src/rtmros_common/openrtm_tools --no-warn-unused-cli -DCATKIN_DEVEL_PREFIX=/root/hlab-nxo-setup/overlay_ws/devel/.private/openrtm_tools -DCMAKE_INSTALL_PREFIX=/root/hlab-nxo-setup/overlay_ws/install -DCATKIN_ENABLE_TESTING=OFF; cd -

.................................................................................................................................................................................................................................................................................
Failed     << openrtm_tools:cmake                [ Exited with code 1 ]                                                                                                                                                                                                          
Failed    <<< openrtm_tools                      [ 1.0 seconds ]                                                                                                                                                                                                                 
                                                                                                                                        

This patch has

This PR adds checking the condiition where testing is really enabled or not.

[pazeshun]

@kazuki0824 835a711 seems not good workaround, because the problem is caused by a bug of collada_urdf and will be fixed by ros/collada_urdf#44 or ros/collada_urdf#46.
Please install https://github.com/werner291/collada_urdf/tree/patch-1 or https://github.com/k-okada/collada_urdf/tree/kinetic-devel in your workspace.
If you use rosinstall, you can copy&paste jsk-ros-pkg/jsk_robot@6100e76.

[kazuki0824]

@pazeshun Thanks. the mentioned commit is reverted in 29681bf