K2: add more tests about false overrides

Related to KT-53197

compiler/testData/ir/irText/firProblems/internalPotentialOverride.kt

@@ -5,6 +5,8 @@
 
 open class A {
     internal open fun foo() : Int = 1
+
+    internal open val bar: Int = 1
 }
 
 // MODULE: m2(m1)
@@ -12,4 +14,6 @@ open class A {
 
 class B : A() {
     fun foo() : String = "OK"
+
+    val bar: Int = 2
 }