Add SepTop to gen serialized results

[hannahbaumann]

Checklist

• Added a news entry

Developers certificate of origin

• I certify that this contribution is covered by the MIT License here and the Developer Certificate of Origin at https://developercertificate.org/.

[github-actions]

No API break detected ✅

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.21%. Comparing base (34988bf) to head (07df00b).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1560      +/-   ##
==========================================
- Coverage   95.26%   93.21%   -2.05%     
==========================================
  Files         172      172              
  Lines       14498    14498              
==========================================
- Hits        13811    13514     -297     
- Misses        687      984     +297     

Flag	Coverage Δ
fast-tests	93.21% <ø> (?)
slow-tests	?

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