fix module name

[nim65s]

Hi,

Running all tests on a clean repo clone --recursive currently fails with:

120/147 Test #147: example-cpp-codegen-crba ...........................Child aborted***Exception:   0.16 sec
Opening file: /pinocchio/models/others/robots/ur_description/urdf/ur5_robot.urdf
Error:   File /pinocchio/models/others/robots/ur_description/urdf/ur5_robot.urdf does not exist
         at line 55 in /build/urdfdom-VnCcob/urdfdom-1.0.4+ds/urdf_parser/src/model.cpp
terminate called after throwing an instance of 'std::invalid_argument'
  what():  The file /pinocchio/models/others/robots/ur_description/urdf/ur5_robot.urdf does not contain a valid URDF model.

It looks like this folder was changed in 8b0d147 , but not everywhere.

[jcarpent]

Thanks for the fix.