Add an explicit dependency to junit-platform-launcher (#166)

* Add an explicit dependency to junit-platform-launcher

It's possible to do this a different way via `useJunitJupiter(libs.versions.junit)`, but dependency bots struggle with this.

See e.g. renovatebot/renovate#29918

* Add the junit-platform-launcher dependency to the version catalog

* Use Junit 6.x now that the jupiter & junit-platform versions are aligned

* Up the toolchain version to allow us to use Junit 6

* Up the JDK version in CI

Author: DavidGregory084

.github/workflows/ci.yml

@@ -32,13 +32,13 @@ jobs:
         id: download-java
         with:
           distribution: temurin
-          java-version: 11
+          java-version: 17
 
       - name: Setup Java JDK
         uses: actions/setup-java@f2beeb24e141e01a676f977032f5a29d81c9e27e # v5.1.0
         with:
           distribution: jdkfile
-          java-version: 11
+          java-version: 17
           jdkFile: ${{ steps.download-java.outputs.jdkFile }}
 
       - name: Setup Gradle

build.gradle.kts

@@ -9,7 +9,7 @@ group = "com.opencastsoftware"
 
 description = "A Prettier Printer for Java"
 
-java { toolchain.languageVersion.set(JavaLanguageVersion.of(11)) }
+java { toolchain.languageVersion.set(JavaLanguageVersion.of(17)) }
 
 dependencies { compileOnlyApi(libs.apiGuardian) }
 
@@ -24,6 +24,7 @@ testing {
                     implementation(libs.equalsVerifier)
                     implementation(libs.toStringVerifier)
                     implementation(libs.apacheCommonsText)
+                    runtimeOnly(libs.junitPlatformLauncher)
                 }
             }
     }

gradle/libs.versions.toml

@@ -6,7 +6,7 @@ gradleJavaConventions = "0.2.0"
 hamcrest = "3.0"
 jacoco = "0.8.8"
 jqwik = "1.9.2"
-junit = "5.11.4"
+junit = "6.0.2"
 toStringVerifier = "1.4.8"
 
 [libraries]
@@ -16,7 +16,8 @@ equalsVerifier = { module = "nl.jqno.equalsverifier:equalsverifier", version.ref
 hamcrest = { module = "org.hamcrest:hamcrest", version.ref = "hamcrest" }
 jqwik = { module = "net.jqwik:jqwik", version.ref = "jqwik" }
 junitJupiter = { module = "org.junit.jupiter:junit-jupiter", version.ref = "junit" }
+junitPlatformLauncher = { module = "org.junit.platform:junit-platform-launcher", version.ref = "junit" }
 toStringVerifier = { module = "com.jparams:to-string-verifier", version.ref = "toStringVerifier" }
 
 [plugins]
-gradleJavaConventions = { id = "com.opencastsoftware.gradle.java-conventions", version.ref = "gradleJavaConventions" }
+gradleJavaConventions = { id = "com.opencastsoftware.gradle.java-conventions", version.ref = "gradleJavaConventions" }