hard coded temp directory causes IPC connection issues to webots due to different lookups

[snoato]

Describe the Bug
A clear and concise description of what the bug is.
Webots uses IPC for communication with external controllers like the webots_ros2 bridge. To enable this, a file is created in the temp directory. Webots looks up the default temp directory for the system (e.g., it might be /var/tmp instead of /tmp on some setups). webots_ros2 only uses /tmp statically. This means that they are unable to communicate unless the code is changed or a symlink is created, since webots_ros2 can't find the IPC file.

Steps to Reproduce

1. Change the default temp directory
2. Run webots_ros2
3. Communication will be impossible

Expected behavior
webots_ros2 should also use the default temp directory (e.g. using python's tempfile.gettempdir().

System

• Webots Version: 2023b
• ROS Version: tested under humble and iron
• Operating System: tested under Ubuntu 22.04 and Fedora 39
• Graphics Card: not relevant here