make tests GPU-compatible

[juliasloan25]

Pursuing the goal of making the coupler entirely GPU-compatible, we should make sure our tests pass on GPU.
part of #390

Current status

passes on GPU?

• aqua
• interfacer
• regridder - not planned
• conservation checker
• bcreader - not planned
• utilities
• time manager
• field exchanger
• flux calculator
• diagnostics - not planned
• postprocessor - not planned
• checkpointer
• coupled_sims experiment test - not planned
• leaderboard
• bucket component test
• atmos component test
• prescribed sea ice component test
• eisenman sea ice component test - not planned
• slab ocean component test
• AMIP debug plots

To do

fixed by removing bycolumn

• flux_calculator_tests.jl
  • uses bycolumn - get_field method not found

other

• debug_amip_plots.jl
  • plotting not GPU compatible
  • might work after applying changes from https://github.com/CliMA/ClimaCoupler.jl/pull/614/files#diff-f01ec1107a04223a7409af03497ce828cdf644af9d40d69a8110831c2142cf27R51-R83

not planned to make GPU-compatible (right now)

• eisenman_seaice_tests.jl
  • planned to be used for academic exercises rather than final coupled model, so GPU compatibility isn't necessary
• regridder_tests.jl
  • will be fixed by ClimaUtilities switch
• bcreader_tests.jl
  • will be fixed by ClimaUtilities switch
• postprocessor_tests.jl
  • NCDataset write (calls Regridder)
• coupledsims experiment test
  • CC.Operators.LinearRemap uses scalar indexing
  • will require change in ClimaCore, or different remapping
• diagnostics_tests.jl
  • args to operation not isbits - FieldVector?
  • not an urgent priority right now - will make GPU compatible in make diagnostics GPU compatible #875

Remaining roadblocks

• file writing
  • diagnostics, checkpointer

modify tests, source code for GPU compatibility

Beta Give feedback

1. tests on GPU - parent usage #748
   🍃 leaf GPU +2
   
2. tests on GPU - remove Fields.bycolumn #736
   🍃 leaf GPU +2
   
3. tests on GPU - plots #750
   🍃 leaf GPU +2
   

[juliasloan25]

Everything we want to get on GPUs is working, so this issue is complete