Updating tracking geometry code for HGTD

This MR includes changes to build the tracking geometry for HGTD and fit its volume. This is done shrinking the ITk tracking geometry volume if needed, i.e. if (flags.GeoModel.Run not in ["RUN1", "RUN2", "RUN3"]). If this is enabled, the maximum extension of the ITk volume in z has to be set in the configuration of the ITk tracking geometry builder.

I have also added a configuration of the VolumeDebugger to dump the entire ATLAS volume, using VolumeDebuggerAtlas.

• Additionally there is some code cleaning and configuration updates.

FYI: @tadej @npetters @nstyles @tstreble @aleopold @dshope