Update dependency io.kotest.multiplatform to v6

| datasource | package                                                       | from  | to          |
| ---------- | ------------------------------------------------------------- | ----- | ----------- |
| maven      | io.kotest.multiplatform:io.kotest.multiplatform.gradle.plugin | 5.9.1 | 6.0.0-LOCAL |

Author: renovate[bot]

gradle/libs.versions.toml

@@ -5,7 +5,7 @@ coroutines = "1.10.1"
 detekt = "1.23.8"
 hikari = "6.3.0"
 kjwt = "1.0.0"
-kotest = "5.9.1"
+kotest = "6.0.0-LOCAL"
 kotest-arrow = "2.0.0"
 kotest-testcontainers = "2.0.2"
 kotlin = "2.1.20"