Give slimes their sex back (not the ERP one) (#14380)

Give slimes their sex back (not the ERP one) (#14380)

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## About the PR
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Gives back the ability for slimes to have a definitive sex. Cosmetic/visual things such as emotes/other stuff use the person's sex and not the gender and I feel like that the removal of slime's having sexes was just to show that the species refactor could handle unsexed species.

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:cl: eclips_e
- fix: Male and female slimes now scream and laugh properly