[Bug] Prevent evolution causing a swap from the second ability to the HA

[DayKev]

What are the changes?

If a Pokémon with their second ability evolves, it will swap to its first ability if the evolution has no second ability, instead of improperly "upgrading" to its hidden ability.

Why am I doing these changes?

I noticed a bug report about the issue
https://discord.com/channels/1125469663833370665/1254274565627187211

cf Bulbapedia

In technical terms, a species' Abilities may be thought of as having separate slots, with an individual Pokémon's non-Hidden slot determined by its personality value. For example, an Eevee — with two non-Hidden Abilities — has Run Away for its first non-Hidden slot, Adaptability for its second, and Anticipation for its Hidden Ability slot. Vaporeon — with only one non-Hidden Ability — can be considered to have Water Absorb for both non-Hidden slots. When a Pokémon evolves, its Ability slot remains the same.

What did change?

src/data/pokemon-species.ts: If a Pokémon doesn't have a second ability, its second ability is set to be the same as its first ability.
The PlayerPokemon.evolve() function is updated to account for Pokémon with 3 abilities evolving into a Pokémon with 2 abilities, including an added parameter preEvolution: PokemonSpeciesForm. Each instance of the function being called is updated accordingly.
Tests were added for the evolve() function.
The starter select UI was updated to account for the duplicated abilities.

Screenshots/Videos

ui.test.mp4

How to test the changes?

Start a run with an Eevee with Adaptability (its second ability) and evolve it with a Fire/Water/Thunder stone. It should now have its first ability (Flash Fire/Water Absorb/Volt Absorb) rather than its hidden ability (Guts/Hydration/Quick Feet).

Checklist

• There is no overlap with another PR?
• The PR is self-contained and cannot be split into smaller PRs?
• Have I provided a clear explanation of the changes?
• Have I tested the changes (manually)?
  • Are all unit tests still passing? (npm run test)
• Are the changes visual?
  • Have I provided screenshots/videos of the changes?