Tests: unmute debugging tests for FIR+JVM_IR

The differences between K1 and K2 are pretty unimportant in these tests.

compiler/testData/debug/stepping/localProperty.kt

@@ -1,5 +1,5 @@
 // IGNORE_BACKEND: WASM
-// IGNORE_BACKEND_K2: JVM_IR
+
 
 // FILE: test.kt
 fun box(): String {
@@ -16,7 +16,11 @@ fun box(): String {
 
 // EXPECTATIONS JVM_IR
 // test.kt:9 box
+// EXPECTATIONS ClassicFrontend JVM_IR
 // test.kt:7 box
+// EXPECTATIONS FIR JVM_IR
+// test.kt:6 box
+// EXPECTATIONS JVM_IR
 // test.kt:12 box
 // test.kt:14 box