Move the sensor blobs for gz-sim under the respectives sensorBlobs

[Nicogene]

Task description

Right now the sensors blobs for gz-sim have been added as XMLBlobs, e.g.:

• https://github.com/icub-tech-iit/ergocub-software/blob/ce6e32b8365a668fd53dba02c60ff013442ffbd3/urdf/creo2urdf/data/ergocub1_1/base_1_1.yaml#L1170-L1176

Instead of being added as sensorBlobs:

• https://github.com/icub-tech-iit/ergocub-software/blob/ce6e32b8365a668fd53dba02c60ff013442ffbd3/urdf/creo2urdf/data/ergocub1_1/base_1_1.yaml#L999-L1003

This has been added in this way in:

• Fix alljoints inertials to work also on gz-sim #250

But I don't recall if there was a reason.

Not a big problem though, having them under sensorBlobs make it more clean

Definition of Done

We moved the sensors XML blobs under sensorBlobs

[Nicogene]

Also the rgbd_camera has been added as XML blob:

• 77593a2