Update kotest to v6.1.9 (#1048)

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

Author: renovate[bot]

gradle/libs.versions.toml

@@ -1,6 +1,6 @@
 [versions]
 exposed = "0.61.0"
-kotest = "6.1.8"
+kotest = "6.1.9"
 kotlin = "2.3.20"
 ktlint = "0.48.1"
 ktor = "3.4.1"