Add missing h_neglect

[NoraLoose]

Looks like the addition of h_neglect is missing in one line for the computation of zonal isopycnal slopes.

Note that is is correctly added in the meridional counterpart:

MOM6/src/core/MOM_isopycnal_slopes.F90

Lines 363 to 370 in 8bf9abb

	hg2A = h(i,j,k-1)*h(i,j+1,k-1) + h_neglect2
	hg2B = h(i,j,k)*h(i,j+1,k) + h_neglect2
	hg2L = h(i,j,k-1)*h(i,j,k) + h_neglect2
	hg2R = h(i,j+1,k-1)*h(i,j+1,k) + h_neglect2
	haA = 0.5*(h(i,j,k-1) + h(i,j+1,k-1)) + h_neglect
	haB = 0.5*(h(i,j,k) + h(i,j+1,k)) + h_neglect
	haL = 0.5*(h(i,j,k-1) + h(i,j,k)) + h_neglect
	haR = 0.5*(h(i,j+1,k-1) + h(i,j+1,k)) + h_neglect

[codecov]

Codecov Report

Merging #98 (f89015b) into dev/gfdl (edd3f9c) will not change coverage.
The diff coverage is 0.00%.

❗ Current head f89015b differs from pull request most recent head 7dfd287. Consider uploading reports for the commit 7dfd287 to get more accurate results

@@            Coverage Diff            @@
##           dev/gfdl      #98   +/-   ##
=========================================
  Coverage     28.98%   28.98%           
=========================================
  Files           246      246           
  Lines         72352    72352           
=========================================
  Hits          20970    20970           
  Misses        51382    51382           

Impacted Files	Coverage Δ
src/core/MOM_isopycnal_slopes.F90	44.93% <0.00%> (ø)

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[Hallberg-NOAA]

I agree that this change should be made for self-consistency. In most existing cases it should not change answers, but it should be noted that it could change answers when there is the run-time-setting that ANGSTROM=0.

[Hallberg-NOAA]

This has passed pipeline testing at https://gitlab.gfdl.noaa.gov/ogrp/MOM6/-/pipelines/15163.