Switch back to JDK 8 for compile time. test are executed with JDK 11.

.github/workflows/build.yml

@@ -16,10 +16,10 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - name: Set up JDK 11
+      - name: Set up JDK 1.8
         uses: actions/setup-java@v1
         with:
-          java-version: 11
+          java-version: 1.8
       - uses: actions/checkout@v2
         with:
           fetch-depth: 0

.github/workflows/release.yml

@@ -14,10 +14,10 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - name: Set up JDK 11
+      - name: Set up JDK 1.8
         uses: actions/setup-java@v1
         with:
-          java-version: 11
+          java-version: 1.8
       - uses: actions/checkout@v2
         with:
           fetch-depth: 0

README.asciidoc

@@ -1,12 +1,11 @@
 = Gradle Test Plugin
-:latestRevision: 4.0.0
+:latestRevision: 4.1.0
 
 [CAUTION]
 ====
 **Breaking Changes!**
 
 This library requires **Gradle >= 7** to work properly.
-Source and target compatibility of the library was changed to **Java 11**
 ====
 
 == Summary

build.gradle.kts

@@ -22,7 +22,7 @@ plugins {
 
 group = "com.intershop.gradle.test"
 description = "Gradle test library - test extension for Gradle plugin builds"
-version = "4.0.0"
+version = "4.1.0"
 
 val sonatypeUsername: String? by project
 val sonatypePassword: String? by project
@@ -33,8 +33,8 @@ java {
 }
 
 configure<JavaPluginConvention> {
-    sourceCompatibility = JavaVersion.VERSION_11
-    targetCompatibility = JavaVersion.VERSION_11
+    sourceCompatibility = JavaVersion.VERSION_1_8
+    targetCompatibility = JavaVersion.VERSION_1_8
 }
 
 // set correct project status
@@ -47,6 +47,10 @@ tasks {
     withType<Test>().configureEach {
         testLogging.showStandardStreams = true
 
+        this.javaLauncher.set( project.javaToolchains.launcherFor {
+            languageVersion.set(JavaLanguageVersion.of(11))
+        })
+
         // Gradle versions for test
         systemProperty("intershop.gradle.versions", "7.0.2")
         systemProperty("intershop.test.base.dir", (File(project.buildDir, "test-working")).absolutePath)