[Audit] RadiationGridComp: pre-migration audit

## Component

**Name:** RadiationGridComp
**Primary file:** `GEOSagcm_GridComp/GEOSphysics_GridComp/@GEOSradiation_GridComp/GEOS_RadiationGridComp.F90`
**Sub-repo:** GEOSradiation_GridComp
**Effort:** M
**MAPL depth:** depth-1

## Current state

- `VERIFY_(` calls: 82
- LOC: 854

## Notes

_None._

## Links

- Parent epic: GEOS-ESM/GEOSgcm_GridComp#1241