Optimize build times (#6418)

authenticator/build.gradle.kts

@@ -260,10 +260,16 @@ protobuf {
     }
 }
 
-tasks {
-    withType<Test> {
-        useJUnitPlatform()
-    }
+tasks.withType<Test>().configureEach {
+    useJUnitPlatform()
+    @Suppress("MagicNumber")
+    forkEvery = 100
+    maxHeapSize = "2g"
+    maxParallelForks = (Runtime.getRuntime().availableProcessors() / 2).coerceAtLeast(1)
+    jvmArgs = jvmArgs.orEmpty() + "-XX:+UseParallelGC" +
+        // Explicitly setting the user Country and Language because tests assume en-US
+        "-Duser.country=US" +
+        "-Duser.language=en"
 }
 
 private fun renameFile(path: String, newName: String) {