fix(deps): update testcontainers-java monorepo to v1.20.6 (#846)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

Diff for: gradle/libs.versions.toml

@@ -49,7 +49,7 @@ jansi = "2.4.1"
 
 # Managed versions appear in the BOM
 managed-opensearch-testcontainers = "2.1.2"
-managed-testcontainers = "1.20.5"
+managed-testcontainers = "1.20.6"
 managed-testcontainers-redis = "1.6.4"
 
 [libraries]