Provide default for kapt language version (#1015)

Otherwise the zip() operator will never compute

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platforms/gradle/foundry-gradle-plugin/src/main/kotlin/foundry/gradle/kgp/KgpTasks.kt

@@ -153,9 +153,9 @@ internal object KgpTasks {
  project.tasks.withType(KaptGenerateStubsTask::class.java).configureEach {
  compilerOptions {
  val zipped =
- foundryProperties.kotlinProgressive.zip(foundryProperties.kaptLanguageVersion) {
- progressive,
-   kaptLanguageVersion ->
+ foundryProperties.kotlinProgressive.zip(
+ foundryProperties.kaptLanguageVersion.orElse(KotlinVersion.DEFAULT)
+ ) { progressive, kaptLanguageVersion ->
  if (kaptLanguageVersion != KotlinVersion.DEFAULT) {
  false
  } else {