Preserve app env in FP tests to benefit from FastJarFS caching

compiler/fir/modularized-tests/tests/org/jetbrains/kotlin/fir/AbstractFullPipelineModularizedTest.kt

@@ -270,6 +270,7 @@ abstract class AbstractFullPipelineModularizedTest : AbstractModularizedTest() {
         val services = Services.Builder().register(CommonCompilerPerformanceManager::class.java, manager).build()
         val collector = TestMessageCollector()
         val result = try {
+            CompilerSystemProperties.KOTLIN_COMPILER_ENVIRONMENT_KEEPALIVE_PROPERTY.value = "true"
             compiler.exec(collector, services, args)
         } catch (e: Exception) {
             e.printStackTrace()