Remove ContainerListener from ServerPlayerMixin

It is no longer a part of the hierarchy, and is causing Mixin to
create technically invalid bytecode as it leaves unimplemented
abstract methods

src/main/java/dev/sapphic/couplings/mixin/ServerPlayerMixin.java

@@ -21,13 +21,12 @@
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.entity.player.Player;
-import net.minecraft.world.inventory.ContainerListener;
 import net.minecraft.world.level.Level;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Unique;
 
 @Mixin(ServerPlayer.class)
-abstract class ServerPlayerMixin extends Player implements ContainerListener, CouplingsPlayer {
+abstract class ServerPlayerMixin extends Player implements CouplingsPlayer {
   @Unique private boolean couplingIgnoresSneaking = true;
 
   ServerPlayerMixin(final Level level, final BlockPos pos, final float spawnAngle, final GameProfile profile) {