UNST-8758: move e_sswnt from e_sbnt to e_ssnt in output

[ZetaTam-dl]

What was done

• Relocate e_sswn and e_sswt from e_sbn and e_sbt to e_ssn and e_sst in writing output
• It should not affect the results (except the output variables in the above).

Evidence of the work done

• Video/figures
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• Clear from the issue description
• Not applicable

Tests

• Tests updated
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• Not applicable

Documentation

• Documentation updated
  <add description of changes if applicable, Issue number>
• Not applicable

Issue link

UNST-8758

[jreyns]

This only affects the linked based transports, not the cell centre ones. I also think that we should do this addition subtraction at the site where they are determined, not at write. The reason for this is that eg the transport over cross-sections will be wrong now.

If you want, we can sit and sort this out