Update dependency com.puppycrawl.tools:checkstyle to v10.20.1

Author: renovate[bot]

gradle/libs.versions.toml

@@ -5,7 +5,7 @@ asciidoctorj-pdf = "2.3.19"
 asciidoctor-plugins = "4.0.3" # Check if workaround in documentation.gradle.kts can be removed when upgrading
 assertj = "3.26.3"
 bnd = "7.0.0"
-checkstyle = "10.20.0"
+checkstyle = "10.20.1"
 eclipse = "4.32.0"
 jackson = "2.18.1"
 jacoco = "0.8.12"