build: update kotlin and adjust language and toolchain versions

Author: silenium-dev

build.gradle.kts

@@ -1,6 +1,8 @@
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
+import org.jetbrains.kotlin.gradle.dsl.KotlinVersion
+
 plugins {
-    kotlin("jvm") version "2.0.0"
-    id("org.jetbrains.kotlinx.atomicfu") version "0.25.0"
+    kotlin("jvm") version "2.0.10"
 }
 
 group = "dev.silenium.playground"
@@ -15,12 +17,9 @@ dependencies {
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutines")
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-debug:$coroutines")
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-jdk8:$coroutines")
-    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-jdk9:$coroutines")
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-reactive:$coroutines")
 
-    implementation("org.jetbrains.kotlinx:atomicfu:0.25.0")
-
-    val kotest = "5.9.0"
+    val kotest = "5.9.1"
     testImplementation("io.kotest:kotest-runner-junit5-jvm:$kotest")
     testImplementation("io.kotest:kotest-assertions-core-jvm:$kotest")
     testImplementation("io.kotest:kotest-property-jvm:$kotest")
@@ -30,6 +29,20 @@ tasks.test {
     useJUnitPlatform()
 }
 
+tasks.compileKotlin {
+    compilerOptions {
+        jvmTarget = JvmTarget.JVM_1_8
+        languageVersion = KotlinVersion.KOTLIN_1_7
+    }
+}
+
+tasks.compileTestKotlin {
+    compilerOptions {
+        jvmTarget = JvmTarget.JVM_1_8
+        languageVersion = KotlinVersion.DEFAULT
+    }
+}
+
 kotlin {
-    jvmToolchain(11)
+    jvmToolchain(8)
 }

src/main/kotlin/dev/silenium/libs/flows/impl/FlowGraphImpl.kt

@@ -91,7 +91,7 @@ internal class FlowGraphImpl(private val coroutineScope: CoroutineScope) :
         elements.forEach(AutoCloseable::close)
     }
 
-    data object CoroutineContextKey : CoroutineContext.Key<CoroutineContextElement>
+    object CoroutineContextKey : CoroutineContext.Key<CoroutineContextElement>
     data class CoroutineContextElement(
         val flowGraph: FlowGraph,
         override val key: CoroutineContext.Key<*> = CoroutineContextKey