🔧 Remove 'shadow' Gradle plugin

Because it is not yet compatible with "JavaApplication.setMainClassName removal": GradleUp/shadow#609

Did the fat JAR with the help of the official user guide:
https://docs.gradle.org/current/userguide/building_java_projects.html#sec:java_packaging

build.gradle.kts

@@ -4,7 +4,6 @@ plugins {
     id("org.jetbrains.kotlin.jvm") version "1.4.20"
     id("se.patrikerdes.use-latest-versions") version "0.2.15"
     id("com.github.ben-manes.versions") version "0.36.0"
-    id("com.github.johnrengelman.shadow") version "6.1.0"
     id("com.adarshr.test-logger") version "2.1.1"
     id("com.diffplug.spotless") version "5.8.2"
     application
@@ -54,3 +53,14 @@ spotless {
         ktlint()
     }
 }
+
+tasks.register<Jar>("uberJar") {
+    archiveClassifier.set("all")
+
+    from(sourceSets.main.get().output)
+
+    dependsOn(configurations.runtimeClasspath)
+    from({
+        configurations.runtimeClasspath.get().filter { it.name.endsWith("jar") }.map { zipTree(it) }
+    })
+}

generate-executable.sh

@@ -4,7 +4,7 @@
 set -e
 
 echo "Building JAR file:"
-./gradlew shadowJar
+./gradlew uberJar
 echo "JAR file has been built! ✅"
 
 echo "Install GraalVM via SDKMAN!:"