Fix T76772: Add Camera Rigs - broken constraint default

Caused by a change in the "Track To" constraint defaults. Behavior was
relying on the defaults, which changed.
Now the axes are explicitly set.

Reviewed by: Julian Eisel

Differential Revision: https://developer.blender.org/D7744

add_camera_rigs/build_rigs.py

@@ -164,6 +164,8 @@ def setup_3d_rig(rig, cam):
     con.subtarget = "Camera"
 
     con = pose_bones['Camera'].constraints.new('TRACK_TO')
+    con.track_axis = 'TRACK_Y'
+    con.up_axis = 'UP_Z'
     con.target = rig
     con.subtarget = "Aim"
     con.use_target_z = True