Is the C48 grid needed? If not can it be removed from testing?

### What is the feature/what would you like to discuss?

In CTSM we currently do NOT support the C48 grid, so I was surprised to see this grid in the CAM testlist.

``` xml












```

If it is needed we'll need to add C48_C48_mt232 to ccs_config, so it would be simpler to change these tests to another grid that is already in place.

### Is there anyone in particular you want to be part of this conversation?

@cacraigucar @nusbaume @peverwhee

### Will this change (regression test) answers?

No

### Will you be implementing this enhancement yourself?

Any CAM SE can do this