patch 9.0.1322: crash when indexing "any" which is an object

Problem:    Crash when indexing "any" which is an object.
Solution:   Check the index is a number.  Do not check the member type of an
            object.  (closes #12019)

src/testdir/test_vim9_class.vim

@@ -253,6 +253,56 @@ def Test_class_member_initializer()
   v9.CheckScriptSuccess(lines)
 enddef
 
+def Test_member_any_used_as_object()
+  var lines =<< trim END
+      vim9script
+
+      class Inner
+        this.value: number = 0
+      endclass
+
+      class Outer
+        this.inner: any
+      endclass
+
+      def F(outer: Outer)
+        outer.inner.value = 1
+      enddef
+
+      var inner_obj = Inner.new(0)
+      var outer_obj = Outer.new(inner_obj)
+      F(outer_obj)
+      assert_equal(1, inner_obj.value)
+  END
+  v9.CheckScriptSuccess(lines)
+
+  lines =<< trim END
+      vim9script
+
+      class Inner
+        this.value: number = 0
+      endclass
+
+      class Outer
+        this.inner: Inner
+      endclass
+
+      def F(outer: Outer)
+        outer.inner.value = 1
+      enddef
+
+      def Test_assign_to_nested_typed_member()
+        var inner = Inner.new(0)
+        var outer = Outer.new(inner)
+        F(outer)
+        assert_equal(1, inner.value)
+      enddef
+
+      Test_assign_to_nested_typed_member()
+  END
+  v9.CheckScriptSuccess(lines)
+enddef
+
 def Test_assignment_with_operator()
   var lines =<< trim END
       vim9script