Drop java 8 support

.github/workflows/ci.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        java: [8, 11, 17, 18] # todo: update to latest Gradle version for Java 21 support
+        java: [11, 17, 18] # todo: update to latest Gradle version for Java 21 support
       fail-fast: false
       max-parallel: 4
     name: JDK ${{ matrix.java }}

build.gradle

@@ -65,8 +65,8 @@ subprojects {
     apply plugin: 'biz.aQute.bnd.builder'
 
     java {
-        sourceCompatibility = JavaVersion.VERSION_1_8
-        targetCompatibility = JavaVersion.VERSION_1_8
+        sourceCompatibility = JavaVersion.VERSION_11
+        targetCompatibility = JavaVersion.VERSION_11
     }
 
     repositories {