Expose trigger for boundingbox_camera sensor

[gsisinna]

Desired behavior

I would like to use a trigger to get snapshots from a boundingbox_camera sensor rather than a continuous stream.
This implementation is already present for the camera sensor, but it is not inherited by boundingbox_camera.

Alternatives considered

Decreasing the sensor update rate and setting <always_on> false </always_on> in the SDF file does not seem to work for the specific case.

Implementation suggestion

The same implementation of CameraSensor:

gz-sensors/src/CameraSensor.cc

Line 166 in d6568aa

/// \brief True if camera is triggered by a topic

gz-sensors/src/CameraSensor.cc

Line 443 in d6568aa

if (_sdf.CameraSensor()->Triggered())

gz-sensors/src/CameraSensor.cc

Line 541 in d6568aa

if (this->dataPtr->isTriggeredCamera &&

gz-sensors/src/CameraSensor.cc

Line 663 in d6568aa

this->isTriggered = true;

Additional context

Thank you!

[mjcarroll]

@gsisinna are you interested in implementing this? We would appreciate it!

[gsisinna]

Sure @mjcarroll, I can start working on this 👍