chore(deps): Update dependency net.kyori:adventure-bom to v4.21.0

Author: renovate[bot]

gradle/libs.versions.toml

@@ -11,7 +11,7 @@ mod-publish-plugin = "0.8.4"
 hangarPublishPlugin = "0.1.3"
 indra = "3.1.3"
 shadow = "8.3.6"
-adventure = "4.20.0"
+adventure = "4.21.0"
 adventurePlatform = "4.3.5-SNAPSHOT"
 adventurePlatformMod = "6.4.0-SNAPSHOT"
 configurate = "4.2.0"