Occasional RVIZ Workbench Plugin Crashing

[marrts]

Per some discussions in #37, there are occasional crashes for unknown reasons related to the tesseract_monitoring and the new event based QT implementation. It is unclear if this is an issue related to this package or tesseract_qt.

[Levi-Armstrong]

If you have a sequence of steps which cause the crash I can go through the same process on tesseract_rviz to see if it crashes. If not I would believe it is something in tesseract_ros2 package.

[marrts]

I haven't been able to reliably cause it yet. Maybe 1 out of 20 times when launching it seems to happen, but I don't think I've seen it happen yet after I've successfully launched it.

[Levi-Armstrong]

How is rviz configured when launch? Is configured as a monitor or urdf?

[marrts]

I've only seen it for monitor, but that's just how I always like to have it, so there's no telling if that is part of the issue.

[rjoomen]

Repeatedly changing from Monitor to URDF and back also causes a crash, though not as quickly as in the first 0.15 attempt, so the fixes by @afrixs certainly have improved things.

[rjoomen]

I've also tested updating the Qt-Advanced-Docking-System dependency to 4.0.3, to see if that has anything to do with the Qt errors or the crashing, but it didn't seem to change anything.