chore: update adventure monorepo to v4.21.0 (#1608)

Author: renovate[bot]

gradle/libs.versions.toml

@@ -69,7 +69,7 @@ bungeecord = "1.21-R0.1-SNAPSHOT"
 limboloohp = "0.7.9-ALPHA"
 
 # platform extensions
-adventure = "4.19.0"
+adventure = "4.21.0"
 modlauncher = "8.1.3"
 npcLib = "3.0.0-beta12"
 packetEvents = "2.7.0"