Further work on refactor to interface based scripts

Plugins/PkmnLib.Plugin.Gen7/Scripts/Terrain/GrassyTerrain.cs

@@ -1,13 +1,13 @@
 namespace PkmnLib.Plugin.Gen7.Scripts.Terrain;
 
 [Script(ScriptCategory.Terrain, "grassy_terrain")]
-public class GrassyTerrain : Script
+public class GrassyTerrain : Script, IScriptChangeBasePower
 {
     private static bool IsAffectedByTerrain(IPokemon pokemon) =>
         !pokemon.IsFloating;
 
     /// <inheritdoc />
-    public override void ChangeBasePower(IExecutingMove move, IPokemon target, byte hit, ref ushort basePower)
+    public void ChangeBasePower(IExecutingMove move, IPokemon target, byte hit, ref ushort basePower)
     {
         // It boosts the power of Grass-type moves used by affected Pokémon by 50% (regardless of whether the target of
         // the move is affected by Grassy Terrain).