Fix StickerUpdate

Author: surajkumar

models/src/main/java/com/javadiscord/jdi/core/models/message/StickerUpdate.java

@@ -7,6 +7,6 @@
 
 @JsonIgnoreProperties(ignoreUnknown = true)
 public record StickerUpdate(
-    @JsonProperty("guildId") long guildId,
+    @JsonProperty("guild_id") long guildId,
     @JsonProperty("stickers") List<Sticker> stickers
 ) {}