Use diktat-runner:shadow as variant (#1875)

- shadow jar as variant is due to Gradle multiply artifacts issue

Author: nulls

diktat-runner/build.gradle.kts

@@ -1,7 +1,5 @@
 import com.saveourtool.diktat.buildutils.configurePublications
 import com.saveourtool.diktat.buildutils.configurePublishing
-import com.github.jengelman.gradle.plugins.shadow.ShadowExtension
-import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
 
 @Suppress("DSL_SCOPE_VIOLATION", "RUN_IN_SCRIPT")  // https://github.com/gradle/gradle/issues/22797
 plugins {
@@ -19,23 +17,31 @@ dependencies {
     implementation(projects.diktatRules)
 }
 
-tasks.named<ShadowJar>("shadowJar") {
+tasks.shadowJar {
     archiveClassifier.set("shadow")
     duplicatesStrategy = DuplicatesStrategy.FAIL
 }
 
+// https://github.com/gradle/gradle/issues/10384#issuecomment-1279708395
+val shadowElement: Configuration by configurations.creating {
+    isCanBeConsumed = true
+    isCanBeResolved = false
+    attributes {
+        attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.LIBRARY))
+        attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage.JAVA_RUNTIME))
+        attribute(Bundling.BUNDLING_ATTRIBUTE, objects.named(Bundling.SHADOWED))
+    }
+    outgoing.artifact(tasks.shadowJar)
+}
+components.named<AdhocComponentWithVariants>("java").configure {
+    addVariantsFromConfiguration(shadowElement) {}
+}
+
 publishing {
     publications {
         create<MavenPublication>("maven") {
             from(components["java"])
         }
-        // it creates a publication for shadowJar
-        create<MavenPublication>("shadow") {
-            // https://github.com/johnrengelman/shadow/issues/417#issuecomment-830668442
-            project.extensions.configure<ShadowExtension> {
-                component(this@create)
-            }
-        }
     }
 }
 configurePublications()