fix: bungeecord version

Author: FllipEis

gradle/libs.versions.toml

@@ -4,7 +4,7 @@ kotlin-coroutines = "1.9.0"
 shadow = "8.3.3"
 
 velocity = "3.4.0-SNAPSHOT"
-bungeecord = "1.20-R0.2-SNAPSHOT"
+bungeecord = "1.21-R0.4"
 
 adventure = "4.19.0"
 adventure-platform = "4.3.4"