Update to Gradle 8 (#3966)

* Update Gradle to 8.5 and all the Gradle plugins where required
* Migrate away from deprecated Gradle API
* Migrate to jvmToolchain, use 11 as the main one
* Apply workarounds for new Gradle constraints, mostly related to implicit dependencies
* Fix a race in CoroutineScheduler.shutdown (exposed by toolchain update):
    * If the thread is in 'NEW' state, then 'isAlive: false' and 'join' returns immediately, meaning that there is a race between thread start and shutdown sequence that makes post-join assertion sporadically fail
* Restructure our build scripts to use .kts conventions only
* Get rid of the deprecated KGP target preset API
* Use the default source-set hierarchy for MPP

---------

Co-authored-by: Dmitry Khalanskiy <[email protected]>

README.md

@@ -173,15 +173,13 @@ commonMain {
 }
 ```
 
-No more additional dependencies are needed, platform-specific artifacts will be resolved automatically via Gradle metadata available since Gradle 5.3.
-
 Platform-specific dependencies are recommended to be used only for non-multiplatform projects that are compiled only for target platform.
 
 #### JS
 
 Kotlin/JS version of `kotlinx.coroutines` is published as 
 [`kotlinx-coroutines-core-js`](https://central.sonatype.com/artifact/org.jetbrains.kotlinx/kotlinx-coroutines-core-js/1.8.0-RC)
-(follow the link to get the dependency declaration snippet) and as [`kotlinx-coroutines-core`](https://www.npmjs.com/package/kotlinx-coroutines-core) NPM package. 
+(follow the link to get the dependency declaration snippet).
 
 #### Native
 

benchmarks/build.gradle.kts

@@ -1,11 +1,11 @@
 /*
- * Copyright 2016-2021 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ * Copyright 2016-2023 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
  */
 
 @file:Suppress("UnstableApiUsage")
 
-import me.champeau.jmh.*
 import org.jetbrains.kotlin.gradle.tasks.*
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 
 plugins {
     id("com.github.johnrengelman.shadow")
@@ -22,18 +22,18 @@ java {
 }
 
 tasks.named<KotlinCompile>("compileJmhKotlin") {
-    kotlinOptions {
-        jvmTarget = "1.8"
-        freeCompilerArgs += "-Xjvm-default=all"
+    compilerOptions {
+        jvmTarget = JvmTarget.JVM_1_8
+        freeCompilerArgs.add("-Xjvm-default=all")
     }
 }
 
 val jmhJarTask = tasks.named<Jar>("jmhJar") {
-    archiveBaseName by "benchmarks"
-    archiveClassifier by null
-    archiveVersion by null
+    archiveBaseName = "benchmarks"
+    archiveClassifier = null
+    archiveVersion = null
     archiveVersion.convention(null as String?)
-    destinationDirectory.set(file("$rootDir"))
+    destinationDirectory = rootDir
 }
 
 tasks {