Refactored tests to Kotlin. (#10034)

Author: AlexeyKuznetsov-DD

buildSrc/build.gradle.kts

@@ -86,25 +86,13 @@ testing {
   @Suppress("UnstableApiUsage")
   suites {
     val test by getting(JvmTestSuite::class) {
-      dependencies {
-        implementation(libs.groovy)
-        implementation(libs.spock.core)
-      }
       targets.configureEach {
         testTask.configure {
           enabled = project.hasProperty("runBuildSrcTests")
         }
       }
     }
 
-    val integTest by registering(JvmTestSuite::class) {
-      dependencies {
-        implementation(gradleTestKit())
-      }
-      // Makes the gradle plugin publish its declared plugins to this source set
-      gradlePlugin.testSourceSet(sources)
-    }
-
     withType(JvmTestSuite::class).configureEach {
       useJUnitJupiter(libs.versions.junit5)
       targets.configureEach {

buildSrc/src/main/kotlin/datadog/gradle/plugin/dump/DumpHangedTestPlugin.kt

@@ -24,6 +24,7 @@ import javax.inject.Inject
 /**
  * Plugin to collect thread and heap dumps for hanged tests.
  */
+@Suppress("unused")
 class DumpHangedTestPlugin : Plugin<Project> {
   companion object {
     private const val DUMP_FUTURE_KEY = "dumping_future"