Fix build warnings

[johanneskbl]

When building my project that depends on this repo I receive the following warnings that stem from wrong interface to setuptools/dist.py:

Starting >>> smach
/usr/lib/python3/dist-packages/setuptools/dist.py:723: UserWarning: Usage of dash-separated 'script-dir' will not be supported in future versions. Please use the underscore name 'script_dir' instead
  warnings.warn(
/usr/lib/python3/dist-packages/setuptools/dist.py:723: UserWarning: Usage of dash-separated 'install-scripts' will not be supported in future versions. Please use the underscore name 'install_scripts' instead
  warnings.warn(
--- stderr: smach                     
/usr/lib/python3/dist-packages/setuptools/dist.py:723: UserWarning: Usage of dash-separated 'script-dir' will not be supported in future versions. Please use the underscore name 'script_dir' instead
  warnings.warn(
/usr/lib/python3/dist-packages/setuptools/dist.py:157: UserWarning: newlines not allowed and will break in the future
  warnings.warn("newlines not allowed and will break in the future")
---
Finished <<< smach

as well as

Starting >>> smach_ros
/usr/lib/python3/dist-packages/setuptools/dist.py:723: UserWarning: Usage of dash-separated 'script-dir' will not be supported in future versions. Please use the underscore name 'script_dir' instead
  warnings.warn(
/usr/lib/python3/dist-packages/setuptools/dist.py:723: UserWarning: Usage of dash-separated 'install-scripts' will not be supported in future versions. Please use the underscore name 'install_scripts' instead
  warnings.warn(
--- stderr: smach_ros                 
/usr/lib/python3/dist-packages/setuptools/dist.py:723: UserWarning: Usage of dash-separated 'script-dir' will not be supported in future versions. Please use the underscore name 'script_dir' instead
  warnings.warn(
/usr/lib/python3/dist-packages/setuptools/dist.py:157: UserWarning: newlines not allowed and will break in the future
  warnings.warn("newlines not allowed and will break in the future")
---
Finished <<< smach_ros [0.52s]

My setup is Ubuntu 22.04 and ROS2 Humble and the standard
python3-setuptools/jammy-updates,jammy-updates,jammy-security,jammy-security,now 59.6.0-1.2ubuntu0.22.04.3 all
python3-colcon-core/jammy,jammy,now 0.20.1+upstream-1
python3-colcon-ros-distro/jammy,jammy 0.1.0-100

It is not breaking anything but would be neat to clean this up such that warnings are reduced.