Update docstrings for `SeaWaterPolynomials.jl`

[jbisits]

Purpose

Updates to some docstrings in SeaWaterPolynomials.jl

Content

• Re word thermal expansion and haline contraction coefficients doscstrings
• Update the $\LaTeX$ strings for thermal expansion and haline contraction coefficients to match Roequt et al. (2015) equations (1) and (2) (with geopotential height $Z$ in place of pressure $p$)
• total density -> density anomaly in $\rho'$ docstring

---

• [x] I have read and checked the items on the review checklist.

References

Roquet et al., "Accurate polynomial expressions for the density and specific volume of seawater using the TEOS-10 standard", Ocean Modelling (2015)

[codecov[bot]]

Codecov Report

Base: 61.66% // Head: 62.90% // Increases project coverage by +1.23% :tada:

Coverage data is based on head (fa5fcdf) compared to base (3e4694e). Patch has no changes to coverable lines.

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Additional details and impacted files

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[glwagner]

I like the original more concise style that leads with the mathematical definition of the constants better than the style introduced in this PR, but I'm ok to have this change esp with better formatting.

[navidcy]

I like the original more concise style that leads with the mathematical definition of the constants better than the style introduced in this PR, but I'm ok to have this change esp with better formatting.

You mean without the explicit mention of what quantity remains constant over differentiation?