FIR: Update test data (nested type aliases)

It's not consistent with FE 1.0, but behavior
for nested type alias is undefined, yet.

compiler/testData/diagnostics/tests/typealias/nestedSubstituted.fir.kt

@@ -0,0 +1,9 @@
+// !DIAGNOSTICS: -UNUSED_VARIABLE -UNUSED_PARAMETER -TOPLEVEL_TYPEALIASES_ONLY
+
+class Pair<T1, T2>(val x1: T1, val x2: T2)
+
+class C<T> {
+    typealias P2 = Pair<T, Int>
+}
+
+val p1: C<String>.P2 = <!TYPE_MISMATCH, TYPE_MISMATCH!>Pair("", 1)<!>

compiler/testData/diagnostics/tests/typealias/nestedSubstituted.kt

@@ -1,4 +1,3 @@
-// FIR_IDENTICAL
 // !DIAGNOSTICS: -UNUSED_VARIABLE -UNUSED_PARAMETER -TOPLEVEL_TYPEALIASES_ONLY
 
 class Pair<T1, T2>(val x1: T1, val x2: T2)