Unignore return and scope cycle tests

lynglib/src/commonTest/kotlin/ReturnStatementTest.kt

@@ -7,7 +7,6 @@ import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 
-@Ignore("TODO(bytecode-only): uses fallback")
 class ReturnStatementTest {
 
     @Test

lynglib/src/commonTest/kotlin/ScopeCycleRegressionTest.kt

@@ -7,7 +7,6 @@ import net.sergeych.lyng.eval
 import kotlin.test.Ignore
 import kotlin.test.Test
 
-@Ignore("TODO(bytecode-only): uses fallback")
 class ScopeCycleRegressionTest {
     @Test
     fun instanceMethodCallDoesNotCycle() = runTest {