Fixed time_profile variable units to be IOOS compliant.

[hvdosser]

The variable time_profile had units that were e.g., 'seconds from 2022-12-01' but with the time changing for each profile. Code has been modified so the correct units will show up for all profiles. This fix also solved an issue where the value of time_profile was showing up as zero for some reason.

[codecov[bot]]

Codecov Report

Base: 77.49% // Head: 77.49% // No change to project coverage :thumbsup:

Coverage data is based on head (918d3aa) compared to base (a32a585). Patch has no changes to coverable lines.

Additional details and impacted files

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[jklymak]

Can we add a test for this. e.g. test that the times are what we want when read back in?

[hvdosser]

I don't think we have any tests for the profile netcdf files right now, or for the gridded files. Do you want me to write one?