Fix extinct species not having preview in auto-evo exporer

[dligr]

Brief Description of What This PR Does

Fixes extinct species not having previews in auto-evo exporer

Related Issues

Fixes #5435

Progress Checklist

Note: before starting this checklist the PR should be marked as non-draft.

• PR author has checked that this PR works as intended and doesn't
  break existing features:
  https://wiki.revolutionarygamesstudio.com/wiki/Testing_Checklist
  (this is important as to not waste the time of Thrive team
  members reviewing this PR)
• Initial code review passed (this and further items should not be checked by the PR author)
• Functionality is confirmed working by another person (see above checklist link)
• Final code review is passed and code conforms to the
  styleguide.

Before merging all CI jobs should finish on this PR without errors, if
there are automatically detected style issues they should be fixed by
the PR author. Merging must follow our
styleguide.

[hhyyrylainen]

I have a few more small code related comments.

[hhyyrylainen]

The code change looks good to me now. I'll assume you've tested this enough as no one else is likely to playtest this and I don't have time right now.