chore(gradle): Convert :internal-api:internal-api-9 to kotlin dsl

chore(build): Migrate :internal-api:internal-api-9 to Kotlin DSL

Author: bric3

internal-api/internal-api-9/build.gradle

@@ -0,0 +1,60 @@
+import groovy.lang.Closure
+
+plugins {
+  `java-library`
+  id("de.thetaphi.forbiddenapis") version "3.8"
+  id("me.champeau.jmh")
+  idea
+}
+
+val minJavaVersionForTests by extra(JavaVersion.VERSION_11)
+
+apply(from = "$rootDir/gradle/java.gradle")
+
+java {
+  toolchain {
+    languageVersion = JavaLanguageVersion.of(11)
+  }
+}
+
+tasks.withType<Javadoc> {
+  javadocTool = javaToolchains.javadocToolFor(java.toolchain)
+}
+
+fun AbstractCompile.setJavaVersion(javaVersionInteger: Int) {
+  (project.extra.get("setJavaVersion") as Closure<*>).call(this, javaVersionInteger)
+}
+
+listOf(JavaCompile::class.java, GroovyCompile::class.java).forEach { compileTaskType ->
+  tasks.withType(compileTaskType) {
+    setJavaVersion(11)
+    sourceCompatibility = JavaVersion.VERSION_1_8.toString()
+    targetCompatibility = JavaVersion.VERSION_1_8.toString()
+  }
+}
+
+val minimumBranchCoverage by extra(0.8)
+val minimumInstructionCoverage by extra(0.8)
+
+dependencies {
+  api(project(":internal-api"))
+
+  testImplementation(project(":dd-java-agent:testing"))
+  testImplementation(libs.slf4j)
+}
+
+tasks.forbiddenApisMain {
+  failOnMissingClasses = false
+}
+
+idea {
+  module {
+    jdkName = "11"
+  }
+}
+
+jmh {
+  jmhVersion = "1.28"
+  duplicateClassesStrategy = DuplicatesStrategy.EXCLUDE
+  jvm = System.getenv("JAVA_11_HOME") + "/bin/java"
+}