[Native][tests] Drop obsolete "kotlin.internal.native.test.useCache" property

native/native.tests/build.gradle.kts

@@ -54,7 +54,6 @@ enum class TestProperty(shortName: String) {
     USE_THREAD_STATE_CHECKER("useThreadStateChecker"),
     GC_TYPE("gcType"),
     GC_SCHEDULER("gcScheduler"),
-    USE_CACHE("useCache"), // TODO: legacy, need to remove it
     CACHE_MODE("cacheMode"),
     EXECUTION_TIMEOUT("executionTimeout");
 
@@ -121,7 +120,6 @@ fun nativeTest(taskName: String, vararg tags: String) = projectTest(taskName, jU
         TestProperty.USE_THREAD_STATE_CHECKER.setUpFromGradleProperty(this)
         TestProperty.GC_TYPE.setUpFromGradleProperty(this)
         TestProperty.GC_SCHEDULER.setUpFromGradleProperty(this)
-        TestProperty.USE_CACHE.setUpFromGradleProperty(this)
         TestProperty.CACHE_MODE.setUpFromGradleProperty(this)
         TestProperty.EXECUTION_TIMEOUT.setUpFromGradleProperty(this)
 

native/native.tests/tests/org/jetbrains/kotlin/konan/blackboxtest/support/NativeTestSupport.kt

@@ -197,15 +197,6 @@ private object NativeTestSupport {
         kotlinNativeTargets: KotlinNativeTargets,
         optimizationMode: OptimizationMode
     ): CacheMode {
-        // TODO: legacy, need to remove it
-        val legacyUseCache = System.getProperty("kotlin.internal.native.test.useCache")?.let(String::toBooleanStrictOrNull)
-        if (legacyUseCache != null) {
-            return if (legacyUseCache)
-                CacheMode.WithStaticCache(kotlinNativeHome, kotlinNativeTargets, optimizationMode, false)
-            else
-                CacheMode.WithoutCache
-        }
-
         val cacheMode = ClassLevelProperty.CACHE_MODE.readValue(
             enforcedProperties,
             CacheMode.Alias.values(),