[Test] Add test for expect nested classes unwrapping

...in type arguments, when they were actualized via
typealias.

^KT-31636

compiler/testData/diagnostics/tests/multiplatform/nestedClassViaActualTypealiasExpandInTypeParam.fir.kt

@@ -0,0 +1,17 @@
+// MODULE: m1-common
+// FILE: common.kt
+<!EXPECT_ACTUAL_INCOMPATIBILITY{JVM}!>expect class Foo {
+    <!EXPECT_ACTUAL_INCOMPATIBILITY{JVM}!>class Inner {
+        <!EXPECT_ACTUAL_MISMATCH{JVM}!>fun foo(p: List<Inner>)<!>
+    }<!>
+}<!>
+
+// MODULE: m2-jvm()()(m1-common)
+// FILE: jvm.kt
+class FooImpl {
+    class Inner {
+        fun foo(p: List<Inner>) {}
+    }
+}
+
+actual typealias <!NO_ACTUAL_CLASS_MEMBER_FOR_EXPECTED_CLASS!>Foo<!> = FooImpl

compiler/testData/diagnostics/tests/multiplatform/nestedClassViaActualTypealiasExpandInTypeParam.kt

@@ -0,0 +1,17 @@
+// MODULE: m1-common
+// FILE: common.kt
+expect class Foo {
+    class Inner {
+        fun foo(p: List<Inner>)
+    }
+}
+
+// MODULE: m2-jvm()()(m1-common)
+// FILE: jvm.kt
+class FooImpl {
+    class Inner {
+        fun foo(p: List<Inner>) {}
+    }
+}
+
+actual typealias <!NO_ACTUAL_CLASS_MEMBER_FOR_EXPECTED_CLASS!>Foo<!> = FooImpl

compiler/testData/diagnostics/tests/multiplatform/nestedClassViaActualTypealiasExpandInTypeParam.ll.kt

@@ -0,0 +1,17 @@
+// MODULE: m1-common
+// FILE: common.kt
+expect class Foo {
+    class Inner {
+        fun foo(p: List<Inner>)
+    }
+}
+
+// MODULE: m2-jvm()()(m1-common)
+// FILE: jvm.kt
+class FooImpl {
+    class Inner {
+        fun foo(p: List<Inner>) {}
+    }
+}
+
+actual typealias <!NO_ACTUAL_CLASS_MEMBER_FOR_EXPECTED_CLASS!>Foo<!> = FooImpl