Merge pull request #160 from KyoriPowered/renovate/patch-release-dependency-changes

chore(deps): Update dependency org.jetbrains.kotlin:kotlin-gradle-plugin to v1.9.21

Author: zml2008

gradle/libs.versions.toml

@@ -10,7 +10,7 @@ indra = "3.1.3"
 jetbrainsAnnotations = "24.0.1"
 jgit = "6.6.0.+" # stay on 5.x series, 6+ requires Java 11
 junit = "5.10.1"
-kotlin = "1.9.20"
+kotlin = "1.9.21"
 mammoth = "1.3.1"
 spotless = "6.21.0"