Tidy up comau_core_launch.py script

[abdullah-ukaea]

Lines 64-66 are not doing anything

CRCOpenROS2Driver/comau_bringup/launch/comau_core.launch.py

Line 65 in ae4f91e

"hardware_type:=",

`

Get robot URDF via xacro

robot_description_content = Command([
    PathJoinSubstitution([FindExecutable(name="xacro")]),
    " ",
    PathJoinSubstitution([
        robot_package,
        "urdf",
        [robot_type,'.urdf.xacro']
    ]),
    " ",
    "hardware_type:=",
    "crcopen",
])

`

This was left over from when we would switch between coppeliasim and real hardware not needed for public release.

Can we clean this up?