Update junit-framework monorepo to v6 (major) (#409)

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

Author: renovate[bot]

gradle/libs.versions.toml

@@ -1,9 +1,12 @@
+[versions]
+junit = "6.0.0"
+
 [libraries]
 gson = "com.google.code.gson:gson:2.13.2"
 hamcrest = "org.hamcrest:hamcrest:3.0"
 jspecify = "org.jspecify:jspecify:1.0.0"
-junit-jupiter = "org.junit.jupiter:junit-jupiter:5.14.0"
-junit-platform = "org.junit.platform:junit-platform-launcher:1.14.0"
+junit-jupiter = { module = "org.junit.jupiter:junit-jupiter", version.ref = "junit" }
+junit-platform = { module = "org.junit.platform:junit-platform-launcher", version.ref = "junit" }
 logback-classic = "ch.qos.logback:logback-classic:1.5.18"
 mockwebserver = "com.squareup.okhttp3:mockwebserver3-junit5:5.1.0"
 telegram-bot-api = "com.github.pengrad:java-telegram-bot-api:9.2.0"