patch 8.2.3422: Vim9: no failure if return type differs from returned var

Problem:    Vim9: no failure if return type differs from returned variable.
Solution:   Copy type when copying a list. (closes #8847)

Author: brammool

src/list.c

@@ -1217,6 +1217,7 @@ list_copy(list_T *orig, int deep, int copyID)
     copy = list_alloc();
     if (copy != NULL)
     {
+	copy->lv_type = orig->lv_type;
 	if (copyID != 0)
 	{
 	    // Do this before adding the items, because one of the items may

src/testdir/test_vim9_func.vim

@@ -438,6 +438,29 @@ def Test_return_invalid()
   CheckScriptFailure(lines, 'E1010:')
 enddef
 
+def Test_return_list_any()
+  var lines =<< trim END
+      vim9script
+      def Func(): list<string>
+        var l: list<any>
+        l->add('string')
+        return l
+      enddef
+      echo Func()
+  END
+  CheckScriptFailure(lines, 'E1012:')
+  lines =<< trim END
+      vim9script
+      def Func(): list<string>
+        var l: list<any>
+        l += ['string']
+        return l
+      enddef
+      echo Func()
+  END
+  CheckScriptFailure(lines, 'E1012:')
+enddef
+
 func Increment()
   let g:counter += 1
 endfunc

src/version.c

@@ -755,6 +755,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3422,
 /**/
     3421,
 /**/