Fix outdated mixins.

Author: Darkhax

common/src/main/java/net/darkhax/splashy/mixin/MixinSplashManager.java

@@ -3,13 +3,15 @@
 import net.darkhax.splashy.Config;
 import net.darkhax.splashy.platform.Services;
 import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.components.SplashRenderer;
 import net.minecraft.client.resources.SplashManager;
 import net.minecraft.client.resources.language.I18n;
 import net.minecraft.server.packs.resources.ResourceManager;
 import net.minecraft.util.profiling.ProfilerFiller;
 import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.Unique;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
@@ -22,6 +24,9 @@
 @Mixin(value = SplashManager.class)
 public class MixinSplashManager {
 
+    @Unique
+    private static final SplashRenderer JARED_BIRTHDAY = new SplashRenderer("Happy Birthday Jared <3");
+
     @Final
     @Shadow
     private List<String> splashes;
@@ -60,15 +65,15 @@ private void apply(List<String> vanillaValues, ResourceManager resources, Profil
         }
     }
 
-    @Inject(method = "getSplash()Ljava/lang/String;", at = @At("RETURN"), cancellable = true)
-    private void getSplash(CallbackInfoReturnable<String> cir) {
+    @Inject(method = "getSplash()Lnet/minecraft/client/gui/components/SplashRenderer;", at = @At("RETURN"), cancellable = true)
+    private void getSplash(CallbackInfoReturnable<SplashRenderer> cir) {
 
         // Special Days
         final LocalDateTime now = LocalDateTime.now();
 
         if (now.getMonth() == Month.JUNE && now.getDayOfMonth() == 29) {
 
-            cir.setReturnValue("Happy Birthday Jared <3");
+            cir.setReturnValue(JARED_BIRTHDAY);
         }
     }
 }