Negative xarea computed with make_coupler_mosaic in Test04

[mlee03]

Describe the bug
Negative exchange grid areas are computed with make_coupler_mosaic_parallel in unit test Test04-grid_coupled_nest.sh.
I'm not sure if this is an expected/known behavior or not...

To Reproduce
run Test04-grid_coupled_nest.sh and look at the output. The output will say
make_coupler_mosaic: one row is added to the south end to cover the globe
error: xarea<0, -431.726873error: xarea<0, -223.208796

Expected behavior
Areas should not be negative?

System Environment
On the AMDBox with NVHPC compiler and MPICH

Additional context