[K2] Forbid to use "get class" in the context of string concat and equality

#KT-63941 Fixed

compiler/testData/diagnostics/tests/modifiers/const/kClassInEquals.kt

@@ -0,0 +1,10 @@
+// FIR_IDENTICAL
+annotation class Anno(val equal: Boolean)
+
+class A
+class B
+
+@Anno(<!ANNOTATION_ARGUMENT_MUST_BE_CONST!>A::class == B::class<!>)
+class C
+
+const val equal = <!CONST_VAL_WITH_NON_CONST_INITIALIZER!>A::class == B::class<!>