* [Test] Add/update test utils
- Add `FieldHelper` which has methods to mock a pokemon's ability
or force a pokemon to be Terastallized
- Add `MoveHelper#use` which can be used to remove the need
for setting pokemon move overrides by modifying the
moveset of the pokemon
- Add `MoveHelper#selectEnemyMove` to make an enemy pokemon
select a specific move
- Add `MoveHelper#forceEnemyMove` which modifies
the pokemon's moveset and then uses `selectEnemyMove`
- Fix `GameManager#toNextTurn` to work correctly in double battles
- Add `GameManager#toEndOfTurn` which advances to the end of the turn
* Update some tests
- Disable broken Good As Gold test
and add `.edgeCase` to Good As Gold
- Fix Powder test
- Update some tests to demonstrate new methods
