[repo] Update to Gradle 8.2.1 version

This Gradle release also fixes 2 security vulnerabilities:
https://docs.gradle.org/8.2.1/release-notes.html

libraries/tools/kotlin-gradle-plugin-idea/src/testFixtures/kotlin/org/jetbrains/kotlin/gradle/idea/testFixtures/tcs/ideaDependencyMatcherBuilders.kt

@@ -25,6 +25,7 @@ fun buildIdeaKotlinDependencyMatchers(notation: Any?): List<IdeaKotlinDependency
 }
 
 fun ideSourceDependency(type: IdeaKotlinSourceDependency.Type, project: Project, sourceSetName: String): IdeaKotlinDependencyMatcher {
+    @Suppress("DEPRECATION") // Should be fixed via https://youtrack.jetbrains.com/issue/KT-58157
     return IdeaKotlinSourceDependencyMatcher(type, project.currentBuildId().name, project.path, sourceSetName)
 }
 

libraries/tools/kotlin-gradle-plugin-idea/src/testFixtures/kotlin/org/jetbrains/kotlin/gradle/idea/testFixtures/utils/proxyUtil.kt

@@ -12,7 +12,7 @@ import org.gradle.tooling.internal.adapter.ProtocolToModelAdapter
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
-inline fun <reified T> createProxyInstance(obj: Any): T {
+inline fun <reified T> createProxyInstance(obj: Any): T? {
     return ProtocolToModelAdapter().adapt(T::class.java, obj)
 }