fix(deps): update testcontainers-java monorepo to v1.20.1

Author: renovate[bot]

gradle/libs.versions.toml

@@ -9,7 +9,7 @@ scylladb_java_driver = "4.18.0.1"
 
 junit = "5.10.3"
 assertj = "3.26.3"
-testcontainers = "1.19.8"
+testcontainers = "1.20.1"
 guava = "33.2.1-jre"
 
 logback = "1.5.6"