add option to prescribe internal wave generation site in grid indices, fixes #1149

[raphaeldussin]

comparing with longitude/latitude does not allow to specify accurately the source of internal wave generation.
the new logical flag allows to pick a point using global indices. The former option is kept for now but could be phased out
later.

[Hallberg-NOAA]

I think that this is a case where slight code changes to improve the error checking on the use of the new parameters (see the specific suggestions in a separate comment) could save some user a lot of grief in the future. @raphaeldussin, please feel free to rebut this suggestion if you think it is more effort than it is worth. Otherwise this PR looks like it will be a useful addition.

[codecov]

Codecov Report

Merging #1448 (b8a2926) into dev/gfdl (7883f63) will decrease coverage by 0.00%.
The diff coverage is 0.00%.

❗ Current head b8a2926 differs from pull request most recent head aabd67e. Consider uploading reports for the commit aabd67e to get more accurate results

@@             Coverage Diff              @@
##           dev/gfdl    #1448      +/-   ##
============================================
- Coverage     29.13%   29.13%   -0.01%     
============================================
  Files           235      235              
  Lines         71025    71039      +14     
============================================
  Hits          20694    20694              
- Misses        50331    50345      +14     

Impacted Files	Coverage Δ
...meterizations/vertical/MOM_internal_tide_input.F90	0.00% <0.00%> (ø)

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[raphaeldussin]

@Hallberg-NOAA the last changes implement the proposed improvements. ready to merge on my end

[Hallberg-NOAA]

I think that there should be one more minor addition to this PR. There is a test to see if the (x,y) test source locations are being set and CS%int_tide_use_glob_ij == .true., and that test looks perfect, but I think that there should also be a test to see if the (i,j) test source locations are being set and CS%int_tide_use_glob_ij == .false..

[raphaeldussin]

agreed! and added!

[marshallward]

Gaea regression: https://gitlab.gfdl.noaa.gov/ogrp/MOM6/-/pipelines/13332 ✔️